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Ethanol Exposure (ethanol + exposure)
Kinds of Ethanol Exposure Selected AbstractsDifferential Effects of Acute and Chronic Ethanol Exposure on Orexin Expression in the Perifornical Lateral HypothalamusALCOHOLISM, Issue 5 2010Irene Morganstern Background:, Recent reports support the involvement of hypothalamic orexigenic peptides in stimulating ethanol intake. Our previous studies have examined the effects of ethanol on hypothalamic peptide systems of the paraventricular nucleus (PVN) and identified a positive feedback loop in which PVN peptides, such as enkephalin and galanin, stimulate ethanol intake and ethanol, in turn, stimulates the expression of these peptides. Recently, orexin (OX), a peptide produced mainly by cells in the perifornical lateral hypothalamus (PFLH), has been shown to play an important role in mediating the rewarding aspects of ethanol intake. However, there is little evidence showing the effects that ethanol itself may have on the OX peptide system. In order to understand the feedback relationship between ethanol and the OX system, the current investigation was designed to measure OX gene expression in the PFLH following acute as well as chronic ethanol intake. Methods:, In the first experiment, Sprague,Dawley rats were trained to voluntarily consume a 2 or 9% concentration of ethanol, and the expression of OX mRNA in the PFLH was measured using quantitative real-time polymerase chain reaction (qRT-PCR). The second set of experiments tested the impact of acute oral gavage of 0.75 and 2.5 g/kg ethanol solution on OX expression in the PFLH using qRT-PCR, as well as radiolabeled in situ hybridization. Further tests using digoxigenin-labeled in situ hybridization and immunofluorescence histochemistry allowed us to more clearly distinguish the effects of acute ethanol on OX cells in the lateral hypothalamic (LH) versus perifornical (PF) regions. Results:, The results showed chronic consumption of ethanol versus water to dose-dependently reduce OX mRNA in the PFLH, with a larger effect observed in rats consuming 2.5 g/kg/d (,70%) or 1.0 g/kg/d (,50%) compared to animals consuming 0.75 g/kg/d (,40%). In contrast to chronic intake, acute oral ethanol compared to water significantly enhanced OX expression in the PFLH, and this effect occurred at the lower (0.75 g/kg) but not higher (2.5 g/kg) dose of ethanol. Additional analyses of the OX cells in the LH versus PF regions identified the former as the primary site of ethanol's stimulatory effect on the OX system. In the LH but not the PF, acute ethanol increased the density of OX-expressing and OX-immunoreactive neurons. The increase in gene expression was detected only at the lower dose of ethanol (0.75 g/kg), whereas the increase in OX peptide was seen only at the higher dose of ethanol (2.5 g/kg). Conclusion:, These results lead us to propose that OX neurons, while responsive to negative feedback signals from chronic ethanol consumption, are stimulated by acute ethanol administration, most potently in the LH where OX may trigger central reward mechanisms that promote further ethanol consumption. [source] Intensity and Duration of Chronic Ethanol Exposure Is Critical for Subsequent Escalation of Voluntary Ethanol Drinking in MiceALCOHOLISM, Issue 11 2009William C. Griffin III Background:, Excessive alcohol drinking continues to be an important health problem. Recent studies from our laboratory and others have demonstrated that animal models of ethanol dependence and relapse can contribute to understanding factors that contribute to excessive drinking. In this study, we tested the hypothesis that the amount and duration of ethanol exposure is critical for promoting the escalation in drinking by mice given access to ethanol in a limited access paradigm. Methods:, We used several methods of chronic intermittent ethanol exposure in male C57BL/6J mice that would vary in the amount and duration of exposure to ethanol as indicated by blood ethanol concentrations (BEC). After establishing baseline drinking in the mice using a 2 hours, 2 bottle choice drinking paradigm, each study involved alternating between periods of ethanol exposure and periods of limited access to ethanol (1 cycle) for a total of 3 cycles. In Study 1, mice were allowed extended access (16 hours) to ethanol for oral consumption or remained in the home cage. In Study 2, the ethanol exposure consisted of intragastric gavage of increasing doses of ethanol or isocaloric sucrose as the control. Study 3 compared intragastric gavage combined with pyrazole, an alcohol dehydrogenase inhibitor, with vapor inhalation of ethanol using procedures known to lead to increased drinking in mice. Finally, Study 4 was a retrospective review of several studies conducted in our laboratory using inhalation procedures. The retrospective review encompassed a range of postvapor chamber BEC values and ethanol intakes that would allow a relationship between increased drinking and BEC to be examined. Results:, Allowing mice to drink for longer periods of time did not cause increased drinking in subsequent limited access sessions. Likewise, gastric intubation of ethanol which produced high BEC (>300 mg/dl) with or without pyrazole did not increase drinking. Only the vapor inhalation procedure, which was associated with sustained BEC above 175 mg/dl for the entire exposure period resulted in increased drinking. The retrospective study provided further evidence that sustained BEC levels above 175 mg/dl was critical to the escalation in drinking. Conclusions:, We found that the intensity (amount) and duration of ethanol exposure, indexed by BEC, is critical to produce increased drinking in mice. Specifically, BEC must regularly exceed 175 mg/dl for the escalation in drinking to occur. Future studies will examine neurobiological adaptations that may underlie the increased drinking behavior caused by chronic intermittent ethanol exposure. [source] Schedule of Passive Ethanol Exposure Affects Subsequent Intragastric Ethanol Self-InfusionALCOHOLISM, Issue 11 2009Tara L. Fidler Background:, Many studies have shown that chronic ethanol exposure can enhance later self-administration of ethanol, but only a few studies have identified critical parameters for such exposure. The present studies examined temporal and other parameters of chronic ethanol exposure on subsequent intragastric (IG) self-infusion of ethanol. Methods:, Sprague,Dawley rats implanted with IG catheters were passively infused with ethanol for 5 to 6 days and then allowed to self-infuse ethanol or water using a procedure in which infusions were contingent upon licking fruit-flavored solutions. Experiment 1 examined the time interval between consecutive periods of passive infusion (Massed Group: 12 hours vs. Spaced Group: 36 hours). Experiment 2 studied the interval between the final passive infusion and onset of self-infusion (12 vs. 36 hours). Finally, Experiment 3 tested the effect of inserting self-infusion days within the passive infusion phase. Results:, Passive ethanol exposure on consecutive days induced relatively large amounts of ethanol self-infusion (4.1 to 7.9 g/kg/d). Increasing the duration of the ethanol-free interval between periods of passive exposure to 36 hours significantly reduced ethanol self-infusion (2.2 g/kg/d; Exp. 1). The time delay between the last passive ethanol exposure and onset of self-infusion had no effect on self-infusion (Exp. 2). Moreover, inserting no-choice self-infusion days between the last few passive exposure days did not increase self-infusion (Exp. 3). Conclusions:, Measurement of withdrawal signs indicated that Massed passive exposure produced stronger dependence than Spaced passive exposure, suggesting that enhanced ethanol self-infusion in Massed Groups might be explained by the opportunity for greater negative reinforcement by ethanol. Although enhanced negative reinforcement might also explain why the Massed Group showed a weaker aversion for the ethanol-paired flavor than the Spaced Group, this observation could also be explained by the development of greater tolerance to ethanol's aversive pharmacological effects in the Massed Group. [source] A Single, Moderate Ethanol Exposure Alters Extracellular Dopamine Levels and Dopamine D2 Receptor Function in the Nucleus Accumbens of Wistar RatsALCOHOLISM, Issue 10 2009Kelle M. Franklin Background:, The nucleus accumbens (NAc) has been implicated in the neurochemical effects of ethanol (EtOH). Evidence suggests that repeated EtOH exposures and chronic EtOH drinking increase dopamine (DA) neurotransmission in the NAc due, in part, to a reduction in D2 autoreceptor function. The objectives of the current study were to evaluate the effects of a single EtOH pretreatment and repeated EtOH pretreatments on DA neurotransmission and D2 autoreceptor function in the NAc of Wistar rats. Methods:, Experiment 1 examined D2 receptor function after a single intraperitoneal (i.p.) injection or repeated i.p. injections of 0.0, 0.5, 1.0, or 2.0 g/kg EtOH to female Wistar rats. Single EtOH pretreatment groups received 1 daily i.p. injection of 0.9% NaCl (saline) for 4 days, followed by 1 day of saline or EtOH administration; repeated EtOH pretreatment groups received 5 days of saline or EtOH injections. Reverse microdialysis experiments were conducted to determine the effects of local perfusion with the D2 -like receptor antagonist (-)sulpiride (SUL; 100 uM), on extracellular DA levels in the NAc. Experiment 2 evaluated if pretreatment with a single, moderate (1.0 g/kg) dose of EtOH would alter levels and clearance of extracellular DA in the NAc, as measured by no-net-flux (NNF) microdialysis. Subjects were divided into the EtOH-naïve and the single EtOH pretreated groups from Experiment 1. Results:, Experiment 1: Changes in extracellular DA levels induced with SUL perfusion were altered by the EtOH dose (p < 0.001), but not the number of EtOH pretreatments (p > 0.05). Post-hoc analyses indicated that groups pretreated with single or repeated 1.0 g/kg EtOH showed significantly attenuated DA response to SUL, compared with all other groups (p < 0.001). Experiment 2: Multiple linear regression analyses yielded significantly (p < 0.05) higher extracellular DA concentrations in the NAc of rats receiving EtOH pretreatment, compared with their EtOH-naïve counterparts (3.96 ± 0.42 nM and 3.25 ± 0.23 nM, respectively). Extraction fractions were not significantly different between the 2 groups. Conclusions:, The present results indicate that a single EtOH pretreatment at a moderate dose can increase DA neurotransmission in the NAc due, in part, to reduced D2 autoreceptor function. [source] Persistent Deficits in Heart Rate Response Habituation Following Neonatal Binge Ethanol ExposureALCOHOLISM, Issue 9 2009Katherine C. Morasch Background:, We have previously shown that the rate of habituation of the heart rate orienting response to a novel odor in rats is negatively affected by neonatal ethanol exposure. Thus far, however, only young rats (16 days of age) have been tested. Given the persistence of attention and memory problems evident in humans exposed to ethanol in utero, the purpose of this experiment was to examine the longer-term consequences of ethanol exposure on response habituation. Methods:, Ethanol (5.25 g/kg/d) was administered intragastrically to male and female Sprague-Dawley rats on postnatal days (PD) 4 to 9, and controls were given sham intubations. Animals were tested for heart rate orienting and response habituation to a novel olfactory stimulus (amyl acetate) on PD 16, 23, or 30. Results:, Animals tested on PD 16 or 23 showed normal heart rate deceleration to the novel odor, a measure of the orienting response. However, ethanol-treated subjects showed impaired response habituation compared with sham controls. While controls exhibited complete habituation within 4 to 5 trials, ethanol-treated animals continued to respond throughout the testing session, with little decrement in heart rate response magnitude across 10 stimulus presentations. A different pattern of responding was observed in animals tested during adolescence (PD 30). Control animals failed to show the typical heart rate decrease indicative of orienting, and instead showed a tendency toward tachycardia. In contrast, ethanol-treated animals tested on PD 30 showed orienting bradycardia that persisted for several trials. Conclusions:, These data suggest that there are relatively long-term consequences of neonatal ethanol exposure on nonassociative memory. This impairment in habituation may be relevant to the distractibility and poor focused attention that is pervasive among humans diagnosed with fetal alcohol spectrum disorders. [source] Circadian Timing of Ethanol Exposure Exerts Enduring Effects on Subsequent Ad Libitum Consumption in C57 MiceALCOHOLISM, Issue 7 2009Jennifer L. Trujillo Background:, There is a daily rhythm in the voluntary intake of ethanol in mice, with greatest consumption in the early night and lowest intake during the day. The role of daily timing of ethanol exposure on the development and control of long-term ethanol self-administration has been neglected. The present study examines these issues using C57BL/6J mice. Methods:, Mice were repeatedly exposed to 10% ethanol for 2 hours early in the night or day for several weeks. Subsequently, ethanol was available at the opposite time (Expt 1) or 24 hours daily (Expts 1 and 2). Lick sensors recorded the patterns of drinking activity in Experiment 2. Results:, Mice exposed to ethanol during the night drink more than mice exposed during the day. Prior history did not affect ethanol intake when the schedule was reversed. Under 24-hour exposure conditions, mice with a history of drinking during the night consumed significantly more than mice drinking during the day. The circadian patterns of drinking were not altered. Conclusions:, These results demonstrate that the daily timing of ethanol exposure exerts enduring effects of self-administration of ethanol in mice. Understanding how circadian rhythms regulate ethanol consumption may be valuable for modifying subsequent intake. [source] Effects of Prenatal Ethanol Exposure on Hypothalamic-Pituitary-Adrenal Function Across the Estrous CycleALCOHOLISM, Issue 6 2009Ni Lan Background:, Rats prenatally exposed to ethanol (E) typically show increased hypothalamic-pituitary-adrenal (HPA) responses to stressors in adulthood. Importantly, prenatal ethanol may differentially alter stress responsiveness in male and female offspring, suggesting a role for the gonadal hormones in mediating the effects of ethanol on HPA activity. We investigated the role of ethanol-induced changes in hypothalamic-pituitary-gonadal (HPG) activity in the differential HPA regulation observed in E compared to control females across the estrous cycle. Methods:, Peripheral hormones and changes in central neuropeptide mRNA levels were measured across the estrous cycle in adult female offspring from E, pair-fed (PF) and ad libitum-fed control (C) dams. Results:, Ethanol females showed normal estrous cyclicity (vaginal smears) but delayed sexual maturation (vaginal opening). Both HPG and HPA activity were differentially altered in E (and in some cases, PF) compared to control females as a function of estrous cycle stage. In relation to HPG activity, E and PF females had higher basal and stress estradiol (E2) levels in proestrus compared to other phases of the cycle, and decreased GnRH mRNA levels compared to C females in diestrus. Further, E females had greater variation in LH than PF and C females across the cycle, and in proestrus, only E females showed a significant LH increase following stress. In relation to HPA activity, both basal and stress CORT levels and overall ACTH levels were greater in E than in C females in proestrus. Furthermore, AVP mRNA levels were increased overall in E compared to PF and C females. Conclusions:, These data demonstrate ethanol-induced changes in both HPG and HPA activity that are estrous phase-specific, and support the possibility that changes in HPA activity in E females may reflect differential sensitivity to ovarian steroids. E females appear to have an increased HPA sensitivity to E2, and a possible shift toward AVP regulation of HPA activity. That PF were similar to E females on some measures suggests that nutritional effects of diet or food restriction played a role in mediating at least some of the changes observed. [source] Dietary Zinc Supplementation Throughout Pregnancy Protects Against Fetal Dysmorphology and Improves Postnatal Survival After Prenatal Ethanol Exposure in MiceALCOHOLISM, Issue 4 2009Brooke L. Summers Background:, We have previously demonstrated that ethanol teratogenicity is associated with metallothionein-induced fetal zinc (Zn) deficiency, and that maternal subcutaneous Zn treatment given with ethanol in early pregnancy prevents fetal abnormalities and spatial memory impairments in mice. Here we investigated whether dietary Zn supplementation throughout pregnancy can also prevent ethanol-related dysmorphology. Methods:, Pregnant mice were injected with saline or 25% ethanol (0.015 ml/g intraperitoneally at 0 and 4 hours) on gestational day (GD) 8 and fed either a control (35 mg Zn/kg) or a Zn-supplemented diet (200 mg Zn/kg) from GD 0 to 18. Fetuses from the saline, saline + Zn, ethanol and ethanol + Zn groups were assessed for external birth abnormalities on GD 18. In a separate cohort of mice, postnatal growth and survival of offspring from these treatment groups were examined from birth until postnatal day 60. Results:, Fetuses from dams treated with ethanol alone in early pregnancy had a significantly greater incidence of physical abnormalities (26%) compared to those from the saline (10%), saline + Zn (9%), or ethanol + Zn (12%) groups. The incidence of abnormalities in ethanol + Zn-supplemented fetuses was not different from saline-treated fetuses. While ethanol exposure did not affect the number of fetal resorptions or pre- or postnatal weight, there were more stillbirths with ethanol alone, and cumulative postnatal mortality was significantly higher in offspring exposed to ethanol alone (35% deaths) compared to all other treatment groups (13.5 to 20.5% deaths). Mice supplemented with Zn throughout pregnancy had higher plasma Zn concentrations than those in un-supplemented groups. Conclusions:, These findings demonstrate that dietary Zn supplementation throughout pregnancy ameliorates dysmorphology and postnatal mortality caused by ethanol exposure in early pregnancy. [source] Long-Term Ethanol Exposure Impairs Neuronal Differentiation of Human Neuroblastoma Cells Involving Neurotrophin-Mediated Intracellular Signaling and in Particular Protein Kinase CALCOHOLISM, Issue 3 2009Julian Hellmann Background:, Revealing the molecular changes in chronic ethanol-impaired neuronal differentiation may be of great importance for understanding ethanol-related pathology in embryonic development but also in the adult brain. In this study, both acute and long-term effects of ethanol on neuronal differentiation of human neuroblastoma cells were investigated. We focused on several aspects of brain-derived neurotrophic factor (BDNF) signaling because BDNF activates the extracellular signal-regulated kinase (ERK) cascade, promoting neuronal differentiation including neurite outgrowth. Methods:, The effects of ethanol exposure on morphological differentiation, cellular density, neuronal marker proteins, basal ERK activity, and ERK responsiveness to BDNF were measured over 2 to 4 weeks. qRT-PCR and Western blotting were performed to investigate the expression of neurotrophin receptor tyrosin kinase B (TrkB), members of the ERK-cascade, protein kinase C (PKC) isoforms and Raf-Kinase-Inhibitor-Protein (RKIP). Results:, Chronic ethanol interfered with the development of a neuronal network consisting of cell clusters and neuritic bundles. Furthermore, neuronal and synaptic markers were reduced, indicating impaired neuronal differentiation. BDNF-mediated activation of the ERK cascade was found to be continuously impaired by ethanol. This could not be explained by expressional changes monitored for TrkB, Raf-1, MEK, and ERK. However, BDNF also activates PKC signaling which involves RKIP, which finally leads to ERK activation as well. Therefore, we hypothesized that ethanol impairs this branch of BDNF signaling. Indeed, both PKC and RKIP were significantly down-regulated. Conclusions:, Chronic ethanol exposure impaired neuronal differentiation of neuroblastoma cells and BDNF signaling, particularly the PKC-dependent branch. RKIP, acting as a signaling switch at the merge of the PKC cascade and the Raf/MEK/ERK cascade, was associated with neuronal differentiation and significantly reduced in ethanol treatment. Moreover, PKC expression itself was even more strongly reduced. In contrast, members of the Raf-1/MEK/ERK cascade were less affected and the observed changes were not associated with impaired differentiation. Thus, reduced RKIP and PKC levels and subsequently reduced positive feedback on ERK activation provide an explanation for the striking effects of long-term ethanol exposure on BDNF signal transduction and neuronal differentiation, respectively. [source] In Utero Ethanol Exposure Impairs Defenses Against Experimental Group B Streptococcus in the Term Guinea Pig LungALCOHOLISM, Issue 2 2009Theresa W. Gauthier Background:, The effects of fetal alcohol exposure on the risks of neonatal lung injury and infection remain under investigation. The resident alveolar macrophage (AM) is the first line of immune defense against pulmonary infections. In utero ethanol (ETOH) exposure deranges the function of both premature and term guinea pig AM. We hypothesized that fetal ETOH exposure would increase the risk of pulmonary infection in vivo. Methods:, We developed a novel in vivo model of group B Streptococcus (GBS) pneumonia using our established guinea pig model of fetal ETOH exposure. Timed-pregnant guinea pigs were pair fed ±ETOH and some were supplemented with the glutathione (GSH) precursor S -adenosyl-methionine (SAM-e). Term pups were given GBS intratracheally while some were pretreated with inhaled GSH prior to the experimental GBS. Neonatal lung and whole blood were evaluated for GBS while isolated AM were evaluated using fluorescent microscopy for GBS phagocytosis. Results:, Ethanol-exposed pups demonstrated increased lung infection and sepsis while AM phagocytosis of GBS was deficient compared with control. When SAM-e was added to the maternal diet containing ETOH, neonatal lung and systemic infection from GBS was attenuated and AM phagocytosis was improved. Inhaled GSH therapy prior to GBS similarly protected the ETOH-exposed pup from lung and systemic infection. Conclusions:, In utero ETOH exposure impaired the neonatal lung's defense against experimental GBS, while maintaining GSH availability protected the ETOH-exposed lung. This study suggested that fetal alcohol exposure deranges the neonatal lung's defense against bacterial infection, and support further investigations into the potential therapeutic role for exogenous GSH to augment neonatal AM function. [source] Acute Ethanol Exposure Combined With Burn Injury Enhances IL-6 Levels in the Murine IleumALCOHOLISM, Issue 10 2007Michael T. Scalfani Background:, Recent studies suggest that ethanol use imposes a greater risk of trauma-associated intestinal injury than trauma alone. The initiating and regulatory factors for multiple organ dysfunction syndromes are not well defined, yet evidence points to the gut as a possible trigger of the systemic inflammatory cascade as well as a potential source of cytokines. In the current study, we hypothesized that ethanol administration would alter cytokine levels and intestinal infiltration by neutrophils within the ileum of mice exposed to burn injury (15% total body surface of dorsal skin). Methods:, Ileal samples were collected for histological assessment, myeloperoxidase quantitation and the protein presence of tumor necrosis factor alpha (TNF,), interleukin (IL-) 6, macrophage inflammatory protein-2 (MIP-2; CXCL2) and the anti-inflammatory cytokine, IL-10. Additional ileal tissue samples were examined for localization of the IL-6 immunoreactivity. Results:, We did not detect statistically significant cytokine/chemokine differences (MIP-2 and IL-10) between sham control and treatment conditions at either 2 or 24 hours. However, there was a significant decrease in TNF, at 24 hours in both burn injury alone and in combination with ethanol treatment conditions (p < 0.05). In addition, there was an increase in IL-6 levels at 24 hours in intestinal tissue obtained from mice subjected to a combination of acute ethanol and burn injury, compared to the mice receiving burn or sham injury (p < 0.001). Ileal homogenate increases in IL-6 at 24 hours were concurrent with decreased villus height in the ileum, but no discernable changes in neutrophil infiltration (myeloperoxidase activity levels) at either 2 or 24 hours. Additional immunocytochemical localization studies of ileal tissue revealed that there was a substantial increase of IL-6 in intestinal enterocytes subjected to both burn injury alone, or in combination with acute ethanol exposure. Conclusions:, The present study suggests that acute ethanol exposure combined with burn injury enhances levels of IL-6 protein in the ileum. The enhanced levels of ileal IL-6 are likely due to enterocyte production of the cytokine. [source] Difluoromethylornithine Decreases Long-Lasting Protein Oxidation Induced by Neonatal Ethanol Exposure in the Hippocampus of Adolescent RatsALCOHOLISM, Issue 5 2007Carlos Fernando Mello Background: Ethanol exposure and withdrawal during central nervous system development can cause oxidative stress and produce severe and long-lasting behavioral and morphological alterations in which polyamines seem to play an important role. However, it is not known if early ethanol exposure causes long-lasting protein oxidative damage and if polyamines play a role in such a deleterious effect of ethanol. Methods: In this study we investigated the effects of early ethanol exposure (6 g/kg/d, by gavage), from postnatal day (PND) 1 to 8, and of the administration of difluoromethylornithine (DFMO, 500 mg/kg, i.p., on PND 8), a polyamine biosynthesis inhibitor, on the extent of oxidative modification of proteins. Indices of oxidative modification of proteins included protein carbonyls, 3-nitrotyrosine (3-NT), and protein bound 4-hydroxynonenal (HNE) in the hippocampus, cerebellum, hypothalamus, striatum, and cerebral cortex of Sprague,Dawley rats at PND 40. Results: Both ethanol and DFMO administration alone increased protein carbonyl immunoreactivity in the hippocampus at PND 40, but the combination of DFMO and ethanol resulted in no effect on protein carbonyl levels. No alterations in the content of protein-bound HNE, 3-NT, or carbonyl were found in any other cerebral structure. Conclusions: These results suggest that the hippocampus is selectively affected by early ethanol exposure and by polyamine synthesis inhibition. In addition, the results suggest a role for polyamines in the long-lasting increase of protein carbonyls induced by ethanol exposure and withdrawal. [source] In Vivo Dysfunction of the Term Alveolar Macrophage After in Utero Ethanol ExposureALCOHOLISM, Issue 2 2007Xiao-Du Ping Background: The effects of in utero alcohol exposure on the immune function of the newborn remain under investigation. Fetal ethanol (ETOH) exposure increases oxidative stress in the developing lung, in part due to decreased availability of the antioxidant glutathione (GSH). We have previously shown that in utero ETOH impairs alveolar macrophage phagocytosis and viability in the premature pup, while maintaining GSH availability with maternal supplementation of S -adenosyl-methionine (SAM) during ETOH ingestion improves macrophage function and viability. We hypothesized that dysfunction of the neonatal alveolar macrophage exposed to ETOH in utero would persist at term gestation. Methods: Using a guinea-pig model of fetal ETOH exposure, timed-pregnant guinea-pigs were pair-fed ETOH±the GSH precursor SAM and the diet continued until spontaneous delivery. Term alveolar macrophages were evaluated using fluorescent microscopy for phagocytosis and apoptosis after in vitro incubation with Staphalococcus aureus. Using an in vivo model of intranasal Staph. aureus inoculation, the in vivo function of the term alveolar macrophage was also investigated using confocal fluorescent analysis. Results: In utero ETOH exposure increased oxidant stress in the alveolar macrophage and decreased phagocytosis and viability in vitro and in vivo. Confocal analysis of phagocytosis in vivo demonstrated a marked impairment of internalization of the bacteria by the ETOH-exposed alveolar macrophage. The addition of SAM during maternal ETOH ingestion prevented loss of alveolar macrophage function and viability in vitro and in vivo. Conclusions: In utero ETOH exposure impairs alveolar macrophage function and viability in vitro and in vivo even at term gestation. The ETOH-induced changes in macrophage function and viability can be ablated with maternal SAM supplementation. Further investigations are required to identify the mechanisms of ETOH-induced derangement of phagocytosis in the neonatal alveolar macrophage and the clinical ramifications of altered immune function after in utero alcohol exposure for the newborn. [source] Fetal Ethanol Exposure Disrupts the Daily Rhythms of Splenic Granzyme B, IFN- ,, and NK Cell Cytotoxicity in AdulthoodALCOHOLISM, Issue 6 2006Alvaro Arjona Background: Circadian (and daily) rhythms are physiological events that oscillate with a 24-hour period. Circadian disruptions may hamper the immune response against infection and cancer. Several immune mechanisms, such as natural killer (NK) cell function, follow a daily rhythm. Although ethanol is known to be a potent toxin for many systems in the developing fetus, including the immune system, the long-term effects of fetal ethanol exposure on circadian immune function have not been explored. Methods: Daily rhythms of cytotoxic factors (granzyme B and perforin), interferon- , (IFN- ,), and NK cell cytotoxic activity were determined in the spleens of adult male rats obtained from mothers who were fed during pregnancy with chow food or an ethanol-containing liquid diet or pair-fed an isocaloric liquid diet. Results: We found that adult rats exposed to ethanol during their fetal life showed a significant alteration in the physiological rhythms of granzyme B and IFN- , that was associated with decreased NK cell cytotoxic activity. Conclusion: These data suggest that fetal ethanol exposure causes a permanent alteration of specific immune rhythms that may in part underlie the immune impairment observed in children prenatally exposed to alcohol. [source] Alterations of Rat Corticostriatal Synaptic Plasticity After Chronic Ethanol Exposure and WithdrawalALCOHOLISM, Issue 5 2006Jian Xun Xia Background: The purpose of this study was to investigate the effects of chronic ethanol exposure (CEE) and withdrawal on corticostriatal plasticity in rats. Methods: We established an animal model of alcoholism using the method of Turchan et al. (1999). A synaptic model of long-term memory (long-term depression, LTD) was used as an index and the striatum, which is related to habit learning, was selected as a target region in the present study. The effects of CEE and withdrawal on the LTD were studied in striatal slices of ethanol-dependent rats using the extracellular recording method. Results: A stable LTD can be induced after high-frequency stimulation (HFS) in the slices of control rats. Chronic ethanol exposure and withdrawal suppressed the induction of corticostriatal LTD to different extents, with the strongest suppressive effects on LTD occurring in the slices of rats exposed to ethanol for 10 days and in those withdrawn from ethanol for 1 day. Notably, 3 days of withdrawal resulted in the shift of corticostriatal synaptic plasticity from LTD to long-term potentiation, and the peak latencies of the population spikes were obviously shortened compared with those of control rats. After 7 days of withdrawal, ethanol's effects tended to disappear. Conclusions: These results suggest that the alterations of corticostriatal synaptic plasticity produced by CEE and withdrawal may play a prominent role in alcohol abuse and alcoholism. [source] Alterations in Circadian Rhythm Phase Shifting Ability in Rats Following Ethanol Exposure During the Third Trimester Brain Growth SpurtALCOHOLISM, Issue 5 2006Hiromi Sakata-Haga Background: Disruptions in sleep and feeding rhythms are among the consequences of prenatal alcohol exposure. Previously, we reported that ethanol exposure during the second trimester equivalent in rats produces long-lasting impairments in circadian system functioning. In the present study, we examined the effects of ethanol exposure during the third trimester equivalent brain growth spurt on the development of the circadian clock system. Methods: Sprague,Dawley male rat pups were exposed to 6.0 g/kg/d ethanol via an artificial rearing procedure on postnatal days (PD) 4 through 9 (EtOH). An artificially reared gastrostomized control group and a normally reared suckle control group were also included. At 10 to 12 weeks of age, wheel-running behavior was measured continuously under a 12-hour/12-hour light/dark (LD) cycle. Thereafter, subjects were exposed to a 6-hour phase delay of the LD cycle, and the ability to adjust to the new LD cycle was evaluated. Results: Before the phase delay, onset time of activity and acrophases of activity in all 3 groups were not significantly different from one another. After the 6-hour LD cycle delay, EtOH subjects were slower to adapt to the new cycle compared with both control groups, as measured by both activity onset and acrophase. Throughout the experiment, activity levels of EtOH subjects tended to be higher compared to both controls. Conclusions: These data demonstrate that ethanol exposure during the third trimester disrupts the ability to synchronize circadian rhythm to light cues. Disruptions in circadian regulation may cause abnormal behavioral rhythmicity, such as disrupted sleep and feeding patterns, as seen in individuals prenatally exposed to ethanol. [source] Chronic Intermittent Ethanol Exposure During Adolescence Blocks Ethanol-Induced Inhibition of Spontaneously Active Hippocampal Pyramidal NeuronsALCOHOLISM, Issue 1 2006Sayaka Tokunaga Background: Binge alcohol drinking among adolescents has been a serious public health problem. A model of binge alcohol, chronic intermittent ethanol exposure (CIEE), during adolescence significantly attenuates ethanol-induced spatial memory deficits in rats. However, the attenuation was absent following a 12-day ethanol-free period. Since spatial memory is hippocampal dependent, a reduction in ethanol-induced spatial memory impairments may be due to a reduction in the ability of ethanol to inhibit the firing rate of single hippocampal pyramidal neurons following CIEE. Methods: Beginning on postnatal day 30 (P30), male adolescent Sprague-Dawley rats (Harlan) were administered 5.0 g/kg ethanol (n=10, CIEE-treated group) or an equivolume saline (n=10, CISE-treated group) every 48 hours for 20 days. Single hippocampal pyramidal neurons from 5 CIEE-treated rats and 5 CISE-treated rats were recorded on the day following completion of the chronic intermittent exposure procedure (animals now P50). Additionally, neurons from 5 CIEE-treated rats and 5 CISE-treated rats were recorded 12 days after the completion of the chronic intermittent exposure procedure (animals now P62). Results: Ethanol exposure during adolescence completely blocked ethanol-induced inhibition of hippocampal pyramidal neurons in rats that were CIEE exposed. However, the effect of CIEE on hippocampal neurophysiology was time dependent. Specifically, neurons recorded from CIEE-treated rats after a 12-day ethanol-free period had similar maximal inhibition as neurons from CISE-treated animals, although the time to reach inhibition was significantly greater in neurons from CIEE-treated rats. Conclusion: Chronic ethanol exposure during adolescence produces a reduction, or tolerance, to ethanol-induced inhibition of hippocampal pyramidal neural activity. Although the tolerance was greatly reversed after a 12-day ethanol-free period, neurons from CIEE animals inhibited slower than neurons from CISE animals. Since the hippocampus is known to be involved not only in spatial memory, but also in many other types of memory formation, the altered hippocampal functions because of CIEE during adolescence should be taken as a serious warning for society. [source] Enhanced Prepulse Inhibition Following Adolescent Ethanol Exposure in Sprague-Dawley RatsALCOHOLISM, Issue 10 2005Craig J. Slawecki Abstract: Objectives: Recent studies have demonstrated that ethanol exposure differentially affects adolescents and adults. The current studies were designed to compare the effects of 2-week exposure to ethanol during adolescence or adulthood on the acoustic startle response (ASR) and prepulse inhibition (PPI) Methods: Male Sprague-Dawley rats were exposed to ethanol vapor 12 hr/d (on from 6 pm to 6 am) for 14 days during adolescence or adulthood. Six days after the cessation of ethanol vapor exposure, the ASR and PPI were assessed. Results: During ethanol treatment, overall blood alcohol levels averaged 230 to 250 mg/dl in the adolescent and adult treatment groups. Assessment of the ASR revealed that latency to startle was more rapid in adolescents than in adults, but ASR latency was not altered by ethanol exposure. In addition, ASR magnitude was lower in adolescents and was decreased in ethanol-exposed rats on startle trials. Ethanol exposure significantly enhanced PPI, but only after adolescent exposure Conclusions: These data further demonstrate a differential sensitivity of adolescents and adults to the effects of ethanol exposure. Specifically, a 2-week period of ethanol exposure during adolescence selectively enhanced PPI, a neurobehavioral index of sensorimotor gating. However, ASR magnitude was decreased by ethanol exposure regardless of age. On the basis of previous studies, the effects of ethanol exposure on PPI data could indicate that adolescent rats exposed to ethanol are more likely to exhibit behavioral inflexibility and that ethanol exposure acts as a more potent physical stressor in adolescent rats. [source] Effects of Neuropeptide Y on Appetitive and Consummatory Behaviors Associated With Alcohol Drinking in Wistar Rats With a History of Ethanol ExposureALCOHOLISM, Issue 4 2005Annika Thorsell Background: Neuropeptide Y (NPY) reduces ethanol intake under free access conditions in Wistar rats with a history of prolonged ethanol vapor exposure. The current study was designed to determine whether NPY differentially alters ethanol-associated appetitive behavior (i.e., lever pressing) or ethanol consumption in Wistar rats with a history of ethanol vapor exposure. Methods: Wistar rats were first trained to self-administer 10% ethanol in a paradigm that provided 25 min of free access to 10% ethanol after completing a 20,lever press response requirement (i.e., an RR20 schedule). After stable level lever pressing was established, operant sessions were suspended during a 9-week period of ethanol vapor exposure. Self-administration sessions were then reinstituted, and a fixed time (FT) schedule of 10% ethanol access was used to assess the effects of ethanol exposure and NPY on lever pressing and drinking behavior. Under the FT schedule, the maximum number of lever presses emitted within 10 min was assessed before providing access to 10% ethanol. Results: Ethanol vapor exposure did not alter patterns of lever pressing under the RR20 schedule, but lever presses emitted under the FT schedule were reduced after ethanol vapor exposure. Ethanol intake was significantly increased after ethanol vapor exposure. NPY significantly reduced ethanol intake but did not significantly reduce lever pressing under the FT schedule. Conclusions: Taken together, these data suggest that chronic ethanol exposure increases ethanol intake without clearly enhancing its reinforcing value. Furthermore, NPY has a greater impact on the consummatory factors mediating ethanol intake than appetitive factors mediating ethanol seeking. [source] A Mouse Model of Prenatal Ethanol Exposure Using a Voluntary Drinking ParadigmALCOHOLISM, Issue 12 2003Andrea M. Allan Background: The incidence of fetal alcohol spectrum disorders is estimated to be as high as 1 in 100 births. Efforts to better understand the basis of prenatal ethanol-induced impairments in brain functioning, and the mechanisms by which ethanol produces these defects, will rely on the use of animal models of fetal alcohol exposure (FAE). Methods: Using a saccharin-sweetened alcohol solution, we developed a free-choice, moderate alcohol access model of prenatal alcohol exposure. Stable drinking of a saccharin solution (0.066%) was established in female mice. Ethanol then was added to the saccharin in increasing concentrations (2%, 5%, 10% w/v) every 2 days. Water was always available, and mice consumed standard pellet chow. Control mice drank saccharin solution without ethanol. After a stable baseline of ethanol consumption (14 g/kg/day) was obtained, females were impregnated. Ethanol consumption continued throughout pregnancy and then was decreased to 0% in a step-wise fashion over a period of 6 days after pups were delivered. Characterization of the model included measurements of maternal drinking patterns, blood alcohol levels, food consumption, litter size, pup weight, pup retrieval times for the dams, and effects of FAE on performance in fear-conditioned learning and novelty exploration. Results: Maternal food consumption, maternal care, and litter size and number were all found to be similar for the alcohol-exposed and saccharin control animals. FAE did not alter locomotor activity in an open field but did increase the time spent inspecting a novel object introduced into the open field. FAE mice displayed reduced contextual fear when trained using a delay fear conditioning procedure. Conclusions: The mouse model should be a useful tool in testing hypotheses about the neural mechanisms underlying the learning deficits present in fetal alcohol spectrum disorders. Moreover, a mouse prenatal ethanol model should increase the opportunity to use the power of genetically defined and genetically altered mouse populations. [source] Dose-Dependent Effects of Prenatal Ethanol Exposure on Synaptic Plasticity and Learning in Mature OffspringALCOHOLISM, Issue 11 2002Daniel D. Savage Background We have observed profound deficits in hippocampal synaptic plasticity and one-trial learning in offspring whose mothers drank moderate quantities of ethanol during pregnancy. In the present study, we examined the question of whether lower maternal blood ethanol concentrations (BECs) could produce functional deficits in offspring. Methods Rat dams consumed either a 2%, 3%, or 5% ethanol liquid diet throughout gestation. Three other groups of dams were pair-fed a 0% ethanol liquid diet, and a seventh group consumed lab chow ad libitum. Adult offspring from each diet group were assigned either to studies of evoked [3H]-D-aspartate (D-ASP) release from hippocampal slices or spatial learning studies using the Morris Water Task. Results Consumption of the 2%, 3%, and 5% ethanol liquid diets produced mean peak maternal BECs of 7, 30 and 83 mg/dL, respectively. Consumption of these ethanol diets had no effect on offspring birthweight, litter size or neonatal mortality. Likewise, evoked D-ASP release from hippocampal slices and performance on a standard version of the Morris Water Task were not affected by prenatal ethanol exposure. By contrast, activity-dependent potentiation of evoked D-ASP release from slices and one-trial learning on a "moving platform" version of the Morris Water Task were markedly reduced in offspring whose mothers consumed the 5% ethanol liquid diet. Intermediate deficits in these two parameters were observed in offspring from the 3% ethanol diet group, whereas offspring from the 2% ethanol diet group were not statistically different than controls. Conclusions We conclude that the threshold for eliciting subtle, yet significant learning deficits in offspring prenatally exposed to ethanol is less than 30 mg/dL. This BEC is roughly equivalent to drinking 1 to 1.5 ounces of ethanol per day. [source] Heritability of the Blood Pressure Response to Acute Ethanol Exposure in Five Inbred Strains of MiceALCOHOLISM, Issue 10 2000Daniel C. Hatton Background: Chronic alcohol consumption is a major risk factor for hypertension. There is evidence in humans that the susceptibility to alcohol-related hypertension may vary based on genotype. As a first step in investigating the genetic basis for alcohol-related hypertension, the current study was designed to assess the heritability of the blood pressure response to acute ethanol exposure by using AKR/J (AK), C57BL/6J (B6), DBA/2J (D2), Balb/cJ (Balb), and A/J (A) mice. Methods: Mean arterial pressure (MAP) was recorded continuously for 24 hr in freely moving mice from an indwelling femoral catheter before we tested the effects of saline or ethanol (2 g/kg ip) on blood pressure. Results: Relative to saline, ethanol caused a pressor response that peaked within 10 min, followed by a decline in MAP. Strain A mice had a significantly greater pressor response to ethanol than other strains and did not show a decline in MAP below baseline. All other strains showed a progressive fall in blood pressure below baseline across the 60 min measurement interval. Heritability was estimated to be 0.62 for the pressor response and 0.64 for the maximal depressor response. Repeated doses of ethanol at 1 hr intervals in A and B6 mice (0,2,1.5,1.5,1.5 g/kg ip) resulted in a dose-dependent increase in MAP in A mice for the first three doses and a dose-dependent decrease in MAP in B6 mice that was independent of blood ethanol concentrations. Conclusion: The results indicate that there is a significant genetic component to the acute blood pressure response to ethanol. [source] Anti-Interleukin-6 Antibody Treatment Restores Cell-Mediated Immune Function in Mice With Acute Ethanol Exposure Before Burn TraumaALCOHOLISM, Issue 9 2000Christine V. Fontanilla Background: Previous studies from this laboratory reported that suppression of cell-mediated immune function was coincident with elevated interleukin (IL)-6 production after acute ethanol exposure before burn trauma, compared with either insult alone. The goal of this study was to investigate whether treatment with an anti-IL-6 antibody could restore immunocompetence in mice subjected to burn trauma with previous exposure to alcohol, as assessed by delayed-type hypersensitivity (DTH) and mitogen-induced splenocyte proliferative responses. Methods: Mice given an ethanol treatment designed to reach a blood alcohol level of 100 mg/dl before a 15% total body surface area burn injury were treated with an anti-IL-6 antibody at 30 min and 24 hr postinjury. Results: Burn/ethanol mice exhibited a 91% suppression of the DTH response (p < 0.01) and a 76% suppression of mitogen-induced splenocyte proliferation (p < 0.01) at 48 hr postinjury, along with increased levels of circulating and splenic macrophage-derived IL-6, compared with all other treatment groups. After anti-IL-6 antibody administration to burn/ethanol mice, there was a 25% (p < 0.05) and 63% (p < 0.01) recovery of the DTH and splenocyte proliferative responses, respectively. Addition of exogenous IL-6 to splenocyte cultures isolated from anti-IL-6 antibody-treated burn/ethanol mice resulted in a 70% inhibition of mitogen-induced proliferative responses (p < 0.03). Conclusions: These data confirm previous findings that burn in combination with acute ethanol exposure suppresses cell-mediated immune function compared with either insult alone. Furthermore, the ability of the anti-IL-6 antibody treatment to improve cellular immune responses in the burn/ethanol group suggests that blocking this cytokine may be beneficial for the ethanol-exposed, thermally injured individual. [source] Binge Pattern Ethanol Exposure in Adolescent and Adult Rats: Differential Impact on Subsequent Responsiveness to EthanolALCOHOLISM, Issue 8 2000Aaron M. White Background: Recent evidence indicates that adolescent animals are more sensitive than adults to the disruptive effects of acute ethanol exposure on spatial learning. It is not yet known whether adolescent animals are also more sensitive than adults to the enduring neurobehavioral effects of repeated ethanol exposure. In this study, animals were exposed to ethanol in a binge-pattern during either adolescence or adulthood. At a time when all subjects were adults, spatial working memory was examined in the absence and presence of an acute ethanol challenge. Methods: Rats were exposed to ethanol (5.0 g/kg intraperitoneally) or isovolumetric saline at 48 hr intervals over 20 days. Exposure began on either postnatal day 30 (adolescent group) or 70 (adult group). Twenty days after the final injection, a time at which all animals were adults, the subjects were tested on an elevated plus maze and then were trained to perform a spatial working memory task on an eight-arm radial maze. At the beginning of each session of training on the working memory task, subjects retrieved food rewards on four of the eight arms. After a delay, subjects were placed on the maze and allowed to retrieve food from the remaining four arms. Results: Prior exposure to ethanol did not influence behavior on the plus maze. Performance of the groups did not differ during acquisition of the spatial working memory task with a 5 min delay or during subsequent testing with a 1 hr delay. However, animals treated with ethanol during adolescence exhibited larger working memory impairments during an ethanol challenge (1.5 g/kg intraperitoneally) than subjects in the other three groups. Conclusions: The findings indicate that binge pattern exposure to ethanol during adolescence enhances responsiveness to the memory-impairing effects of ethanol in adulthood. [source] Pathology of the Olfactory Epithelium: Smoking and Ethanol Exposure,THE LARYNGOSCOPE, Issue 8 2004J Vent MD Abstract Objective: To investigate the effects of tobacco smoke on the olfactory epithelium. Cigarette smoking has been associated with hyposmia; however, the pathophysiology is poorly understood. The sense of smell is mediated by olfactory sensory neurons (OSNs) exposed to the nasal airway, rendering them vulnerable to environmental injury and death. As a consequence, a baseline level of apoptotic OSN death has been demonstrated even in the absence of obvious disease. Dead OSNs are replaced by the mitosis and maturation of progenitors to maintain sufficient numbers of neurons into adult life. Disruption of this balance has been suggested as a common cause for clinical smell loss. This current study will evaluate the effects of tobacco smoke on the olfactory mucosa, with emphasis on changes in the degree of OSN apoptosis. Study Design: A rat model was used to assess the olfactory epithelium after exposure to tobacco smoke. Methods: Rats were exposed to tobacco smoke alone (for 12 weeks), smoke plus dietary ethanol (for the final 5 weeks), or to neither (control). Immunohistochemical analysis of the olfactory epithelium was performed using an antibody to the active form of caspase-3. Positive staining for this form of the caspase-3 enzyme indicates a cell undergoing apoptotic proteolysis. Results: Control rats demonstrated a low baseline level of caspase-3 activity in the olfactory epithelium. In contrast, tobacco smoke exposure triggered a dramatic increase in the degree of OSN apoptosis that affected all stages of the neuronal lineage. Conclusions: These results support the following hypothesis: smell loss in smokers is triggered by increased OSN death, which eventually overwhelms the regenerative capacity of the epithelium. [source] Ethanol exposure during embryogenesis decreases the radial glial progenitorpool and affects the generation of neurons and astrocytesJOURNAL OF NEUROSCIENCE RESEARCH, Issue 3 2006Gemma Rubert Abstract Prenatal ethanol exposure induces functional abnormalities during brain development affecting neurogenesis and gliogenesis. We have previously reported that alcohol exposure during embryogenesis disrupts radial glia (RG) and gliogenesis. Taking into account the new role of RG as neural progenitors, we have investigated whether ethanol affects RG as a neural stem cell. We found that in utero ethanol exposure impairs cell proliferation and decreases neurons and astrocytes generated in cultured RG and in embryonic cerebral cortex. Telencephalic cultures obtained at E12 from ethanol-treated rats displayed a reduction in the proportion of actively dividing RG progenitors, as demonstrated by 5-bromo-2,-deoxyuridine incorporation, and in the percentage of brain lipid binding protein-positive RG. Consistently, neurosphere formation assay from E12 telencephalon showed a reduced number of multipotent progenitor cells in cultures isolated from ethanol-treated rats in comparison with pair-fed control group. Moreover, levels of activated Notch1 and fibroblast growth factor receptor 2, which regulate the maintenance of the progenitor state of RG, are decreased by prenatal ethanol exposure. These findings demonstrate that ethanol reduces the telencephalic RG progenitor pool and its transformation into neurons and astrocytes, which may contribute to an explanation of the defects in brain function often observed in fetal alcohol syndrome. © 2006 Wiley-Liss, Inc. [source] Period 2 Gene Deletion Abolishes ,-Endorphin Neuronal Response to EthanolALCOHOLISM, Issue 9 2010Maria Agapito Background:, Ethanol exposure during early life has been shown to permanently alter the circadian expression of clock regulatory genes and the ,-endorphin precursor proopiomelanocortin (POMC) gene in the hypothalamus. Ethanol also alters the stress- and immune-regulatory functions of ,-endorphin neurons in laboratory rodents. Our aim was to determine whether the circadian clock regulatory Per2 gene modulates the action of ethanol on ,-endorphin neurons in mice. Methods:,Per2 mutant (mPer2Brdml) and wild type (C57BL/6J) mice were used to determine the effect of Per2 mutation on ethanol-regulated ,-endorphin neuronal activity during neonatal period using an in vitro mediobasal hypothalamic (MBH) cell culture model and an in vivo milk formula feeding animal model. The ,-endorphin neuronal activity following acute and chronic ethanol treatments was evaluated by measuring the peptide released from cultured cells or peptide levels in the MBH tissues, using enzyme-linked immunosorbent assay (ELISA). Results:,Per2 mutant mice showed a higher basal level of ,-endorphin release from cultured MBH cells and a moderate increase in the peptide content in the MBH in comparison with control mice. However, unlike wild type mice, Per2 mutant mice showed no stimulatory or inhibitory ,-endorphin-secretory responses to acute and chronic ethanol challenges in vitro. Furthermore, Per2 mutant mice, but not wild type mice, failed to show the stimulatory and inhibitory responses of MBH ,-endorphin levels to acute and chronic ethanol challenges in vivo. Conclusions:, These results suggest for the first time that the Per2 gene may be critically involved in regulating ,-endorphin neuronal function. Furthermore, the data revealed an involvement of the Per2 gene in regulating ,-endorphin neuronal responses to ethanol. [source] Genetic and Environmental Influences on Ethanol Consumption: Perspectives From Preclinical ResearchALCOHOLISM, Issue 6 2010Ricardo M. Pautassi Background:, Alcohol use disorders (abuse and dependence, AUD) are multifactorial phenomena, depending on the interplay of environmental and genetic variables. Method:, This review describes current developments in animal research that may help (a) develop gene therapies for the treatment of alcoholism, (b) understand the permissive role of stress on ethanol intake, and (c) elucidate why exposure to ethanol early in life is associated with a greater risk of AUD. Results:, The polymorphisms found in liver alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) affect the elimination of ethanol and the susceptibility to ethanol intake. A highly active ADH protects against alcoholism, an effect related to a presteady state burst in arterial acetaldehyde. Social stressors, such as repeated early maternal separation or social defeat, exert a permissive effect on ethanol intake, perhaps by altering the normal development of the hypothalamic-pituitary-adrenal axis. Ethanol exposure during gestation, infancy, or adolescence increases the likelihood of AUD later in life. Early perception of ethanol's positive and negative (anti-anxiety) reinforcing effects may play a role in this phenomenon. Conclusions:, The review underscores the advantages of using preclinical animal models of AUD and highlights points of intersection between the topics to help design a more integrated approach for the study of alcohol-related problems. [source] Ethanol Impairs Activation of Retinoic Acid Receptors in Cerebellar Granule Cells in a Rodent Model of Fetal Alcohol Spectrum DisordersALCOHOLISM, Issue 5 2010Ambrish Kumar Background:, Ethanol is the main addictive and neurotoxic constituent of alcohol. Ethanol exposure during embryonic development causes dysfunction of the central nervous system (CNS) and leads to fetal alcohol spectrum disorders. The cerebellum is one of the CNS regions that are particularly vulnerable to ethanol toxic effects. Retinoic acid (RA) is a physiologically active metabolite of vitamin A that is locally synthesized in the cerebellum. Studies have shown that RA is required for neuronal development, but it remains unknown if ethanol impairs RA signaling and thus induces neuronal malformations. In this study, we tested the hypothesis that ethanol impairs the expression and activation of RA receptors in cerebellum and in cerebellar granule cells. Methods:, The cerebellum of ethanol unexposed and exposed pups was used to study the expression of retinoic acid receptors (RARs or RXRs) by immunohistochemistry and by Western blot analysis. We also studied the effect of ethanol on expression of RA receptors in the cerebellar granule cells. Activation of RA receptors (DNA-binding activities) in response to high-dose ethanol was determined by electrophoretic mobility shift and supershift assays. Results:, Findings from these studies demonstrated that ethanol exposure reduced the expression of RAR,/, while it increased the expression of RXR,/, in the cerebellum and in cerebellar granule neurons. Immuno-histological studies further strengthened the expression pattern of RA receptors in response to ethanol. The DNA-binding activity of RARs was reduced, while DNA-binding activity of RXRs was increased in response to ethanol exposure. Conclusion:, For the first time, our studies have demonstrated that high-dose ethanol affects the expression and activation of RA receptors, which could impair the signaling events and induce harmful effects on the survival and differentiation of cerebellar granule cells. Taken together, these findings could provide insight into the treatment options for brain defects caused by excessive ethanol exposure, such as in Fetal Alcohol Spectrum Disorders. [source] Effects of Ethanol on Mouse Embryonic Stem CellsALCOHOLISM, Issue 12 2009Alla Arzumanyan Background:, Fetal alcohol syndrome (FAS) reflects a constellation of congenital abnormalities caused by excess maternal consumption of alcohol. It is likely that interference with embryonic development plays a role in the pathogenesis of the disorder. Ethanol-induced apoptosis has been suggested as a causal factor in the genesis of FAS. Mouse embryonic stem (mES) cells are pluripotent cells that differentiate in vitro to cell aggregates termed embryoid bodies (EBs), wherein differentiation capacity and gene expression profile are similar to those of the early embryo. Methods:, To investigate the effects of ethanol during differentiation, mES cells were cultured on a gelatin surface in the presence of leukemia inhibitory factor which maintains adherent undifferentiated cells or in suspension to promote formation of EBs. All cells were treated (1,6 days) with 80 mM ethanol. The pluripotency and differentiation of mES cells were evaluated by western blotting of stage-specific embryonic antigen (SSEA-1), transcription factors Oct-3/4, Sox-2, and Nanog, using alkaline phosphatase staining. Apoptosis (early to late stages) was assessed by fluorescence-activated cell sorting using TdT-mediated biotin,dUTP nick-end labelling assay and fluorescein isothiocyanate-Annexin V/propidium iodide staining. Results:, Ethanol increased apoptosis during in vitro differentiation of mES cells to EBs, whereas undifferentiated cells were not affected. Ethanol exposure also interfered with pluripotency marker patterns causing an upregulation of SSEA-1 under self-renewal conditions. In EBs, ethanol delayed the downregulation of SSEA-1 and affected the regulation of transcription factors during differentiation. Conclusion:, Our findings suggest that ethanol may contribute to the pathogenesis of FAS by triggering apoptotic pathways during differentiation of embryonic stem cells and deregulating early stages of embryogenesis. [source] | ||||||||||||||||