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Anesthetized Rats (anesthetized + rat)
Selected AbstractsRole of the Neurokinin-1 Receptors in Ejaculation in Anesthetized RatsTHE JOURNAL OF SEXUAL MEDICINE, Issue 1 2009Pierre Clement PhD ABSTRACT Introduction., Several lines of evidence indicate a role for substance P in the control of ejaculation, although its mode of action needs to be clarified. Aim., The effects and sites of action of a selective antagonist for the substance P-preferred receptor (neurokinin-1 receptor subtype; NK1) were investigated in a pharmacological model of ejaculation. Methods., Ejaculation was induced in anesthetized rats by intracerebroventricular (icv) delivery of the dopamine D3 receptor preferring agonist 7-hydroxy-2-(di-N-propylamino)tetralin (7-OH-DPAT). The effects of the selective NK1 antagonist RP67580 on 7-OH-DPAT-induced ejaculation were measured following intraperitoneal (ip), icv, or intrathecal (it) (third lumbar spinal segment; L3) administration. Main Outcome Measures., Intraseminal vesicle pressure (SVP) and electromyogram of the bulbospongiosus muscle (BS) were recorded as physiological markers of emission and expulsion phases of ejaculation, respectively. Results., Upon ip, icv, or it administration, RP67580 significantly reduced the occurrence of ejaculation elicited by 7-OH-DPAT. A mild decrease in the occurrence of SVP and BS responses was observed in rats treated ip with RP67580, whereas only SVP responses were moderately affected following icv or it administration. Conclusion., These results show the multilevel regulation of 7-OH-DPAT-induced ejaculation by NK1 receptors. Clement P, Peeters M, Bernabe J, Laurin M, Alexandre L, and Giuliano F. Role of the neurokinin-1 receptors in ejaculation in anesthetized rats. J Sex Med 2009;6:126,134. [source] Effects of PEEP levels following repeated recruitment maneuvers on ventilator-induced lung injuryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2008S.-C. KO Background: Different levels of positive end-expiratory pressure (PEEP) with and without a recruitment maneuver (RM) may have a significant impact on ventilator-induced lung injury but this issue has not been well addressed. Methods: Anesthetized rats received hydrochloric acid (HCl, pH 1.5) aspiration, followed by mechanical ventilation with a tidal volume of 6 ml/kg. The animals were randomized into four groups of 10 each: (1) high PEEP at 6 cm H2O with an RM by applying peak airway pressure at 30 cm H2O for 10 s every 15 min; (2) low PEEP at 2 cm H2O with RM; (3) high PEEP alone; and (4) low PEEP alone. Results: The mean arterial pressure and the amounts of fluid infused were similar in the four groups. Application of the higher PEEP improved oxygenation compared with the lower PEEP groups (P<0.05). The lung compliance was better reserved, and the systemic cytokine responses and lung wet to dry ratio were lower in the high PEEP than in the low PEEP group for a given RM (P<0.05). Conclusions: The use of a combination of periodic RM and the higher PEEP had an additive effect in improving oxygenation and pulmonary mechanics and attenuation of inflammation. [source] Extravascular Transport of Fluorescently Labeled Albumins in the Rat MesenteryMICROCIRCULATION, Issue 3 2002NORMAN R. HARRIS ABSTRACT Objective: Fluorescently labeled albumin is used frequently as a tracer when monitoring microvascular permeability. Several fluorescent dyes are available for labeling protein, including fluorescein isothiocyanate (FITC) and Texas Red (TR). Because differences in leakage of dye-labeled proteins have been reported, the objective of the present study was to compare the accumulation of these two tracers in interstitium and lymph after the inflammatory event of ischemiareperfusion. Methods: Anesthetized rats were injected intravenously with FITC-labeled albumin (FITC-alb) and TR-labeled albumin (TR-alb) before 30 minutes of mesenteric ischemia. Because the tracers leaked out of the microcirculation after reperfusion, accumulation in the surrounding buffer-superfused tissue, and in separate experiments, accumulation in lymph vessels, was defined as the ratio of tissue-to-plasma and lymph-to-plasma fluorescence. Results: Reperfusion induced a significant increase in tissue-to-plasma fluorescence of FITC-alb; however, no increase was observed for TR-alb. In contrast, lymph-to-plasma fluorescence of TR-alb tended to be greater than FITC-alb. Reperfusion-induced increases in tissue-to-plasma fluorescence of TR-alb occurred only when the superfusate was replaced with mineral oil, in which case tissue-to-plasma TR-alb fluorescence tended to be greater than FITC-alb. Conclusions: Measurement of fluorescently labeled albumin leakage from mesenteric venules depends on the dye used to label the albumin and requires an assessment of losses from the extravascular measuring region. [source] Odor vapor pressure and quality modulate local field potential oscillatory patterns in the olfactory bulb of the anesthetized ratEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2008Tristan Cenier Abstract A central question in chemical senses is the way that odorant molecules are represented in the brain. To date, many studies, when taken together, suggest that structural features of the molecules are represented through a spatio-temporal pattern of activation in the olfactory bulb (OB), in both glomerular and mitral cell layers. Mitral/tufted cells interact with a large population of inhibitory interneurons resulting in a temporal patterning of bulbar local field potential (LFP) activity. We investigated the possibility that molecular features could determine the temporal pattern of LFP oscillatory activity in the OB. For this purpose, we recorded the LFPs in the OB of urethane-anesthetized, freely breathing rats in response to series of aliphatic odorants varying subtly in carbon-chain length or functional group. In concordance with our previous reports, we found that odors evoked oscillatory activity in the LFP signal in both the beta and gamma frequency bands. Analysis of LFP oscillations revealed that, although molecular features have almost no influence on the intrinsic characteristics of LFP oscillations, they influence the temporal patterning of bulbar oscillations. Alcohol family odors rarely evoke gamma oscillations, whereas ester family odors rather induce oscillatory patterns showing beta/gamma alternation. Moreover, for molecules with the same functional group, the probability of gamma occurrence is correlated to the vapor pressure of the odor. The significance of the relation between odorant features and oscillatory regimes along with their functional relevance are discussed. [source] Near-Infrared Mesoporous Silica Nanoparticles for Optical Imaging: Characterization and In Vivo BiodistributionADVANCED FUNCTIONAL MATERIALS, Issue 2 2009Chia-Hung Lee Abstract The characterization of near-infrared (NIR) mesoporous silica nanoparticles (MSN) suitable for in vivo optical imaging with high efficiency is presented. Trimethylammonium groups modified MSN (MSN-TA) with the average size of 50,100,nm was synthesized with incorporation of the TA groups into the framework of MSN. It was further adsorbed with indocyanine green (ICG) by electrostatic attraction to render MSN-TA-ICG as an efficient NIR contrast agent for in vivo optical imaging. The studies in stability of MSN-TA-ICG against pH indicated the bonding is stable over the range from acidic to physiological pH. The in vivo biodistribution of MSN-TA-ICG in anesthetized rat demonstrated a rather strong and stable fluorescence of MSN-TA-ICG that prominent in the organ of liver. Transmission electron microscopy (TEM) imaging and elemental analysis of silicon further manifested the physical and quantitative residences of MSN-TA-ICG in major organs. This is the first report of MSN functionalized with NIR-ICG capable of optical imaging in vivo. [source] Dynamic changes in the direction of the theta rhythmic drive between supramammillary nucleus and the septohippocampal systemHIPPOCAMPUS, Issue 6 2006Bernat Kocsis Abstract Neurons in the supramammillary nucleus (SUM) of urethane-anesthetized rats fire rhythmically in synchrony with hippocampal theta rhythm. As these neurons project to the septum and hippocampus, it is generally assumed that their role is to mediate ascending activation, leading to the hippocampal theta rhythm. However, the connections between SUM and the septohippocampal system are reciprocal; there is strong evidence that theta remains in the hippocampus after SUM lesions and in the SUM after lesioning the medial septum. The present study examines the dynamics of coupling between rhythmic discharge in the SUM and hippocampal field potential oscillations, using the directionality information carried by the two signals. Using directed transfer function analysis, we demonstrate that during sensory-elicited theta rhythm and also during short episodes of theta acceleration of spontaneous oscillations, the spike train of a subpopulation of SUM neurons contains information predicting future variations in rhythmic field potentials in the hippocampus. In contrast, during slow spontaneous theta rhythm, it is the SUM spike signal that can be predicted from the preceding segment of the electrical signal recorded in the hippocampus. These findings indicate that, in the anesthetized rat, SUM neurons effectively drive theta oscillations in the hippocampus during epochs of sensory-elicited theta rhythm and short episodes of theta acceleration, whereas spontaneous slow theta in the SUM is controlled by descending input from the septohippocampal system. Thus, in certain states, rhythmically firing SUM neurons function to accelerate the septal theta oscillator, and in others, they are entrained by a superordinate oscillatory network. © 2006 Wiley-Liss Inc. [source] Medial septal modulation of the ascending brainstem hippocampal synchronizing pathways in the anesthetized ratHIPPOCAMPUS, Issue 1 2006Jesse Jackson Abstract Independent and combined electrical stimulation pairings of the medial septum (MS), posterior hypothalamus (PH), and reticular pontine oralis (RPO) of the brainstem were performed in the acute urethane anesthetized rat, while recording field activity from electrodes in either the stratum oriens or stratum moleculare of the hippocampal formation. Theta frequency and power were measured during independent stimulation of each nuclei and during combined stimulation using three pairings: (1) MS,PH (2) MS,RPO and (3) PH,RPO. Each pairing consisted of parameters known to elicit theta of a high frequency for one nucleus, and parameters known to elicit a low frequency for the second nucleus. This methodology allowed us to observe whether one nucleus preferentially modulated theta activity in the hippocampus in terms of frequency and power. The MS was observed to reset theta frequency in both the upward and downward direction when stimulated in combination with either the PH (Experiment 1) or the RPO (Experiment 2). In Experiment 3 (PH,RPO), the structure receiving the higher intensity stimulation had the predominate effect on theta frequency. With MS stimulation combinations, the power of the elicited theta activity was found to increase over the independent stimulation in some cases during Experiment 1. Likewise, in Experiment 2, the combined stimulation produced a power that in most cases was significantly greater than that measured during the independent stimulations. This effect was not observed with PH and RPO stimulation combinations. The combined stimulation of the PH and RPO yielded a power similar to the independent PH stimulations. The findings support the following conclusions: (1) the major theta generating activity of the ascending brainstem synchronizing pathways involves projections from the RPO to the PH, relayed through the MS, to the hippocampal formation; and (2) that the MS directly controls theta amplitude and secondarily translates the level of ascending brainstem activity into the appropriate frequency of hippocampal theta. © 2005 Wiley-Liss, Inc. [source] MRI tumor characterization using Gd-GlyMe-DOTA-perfluorooctyl-mannose-conjugate (Gadofluorine MÔ), a protein-avid contrast agentCONTRAST MEDIA & MOLECULAR IMAGING, Issue 3 2006Hans-Jürgen Raatschen Abstract The rationale and objectives were to define the MRI tumor-characterizing potential of a new protein-avid contrast agent, Gd-GlyMe-DOTA-perfluorooctyl-mannose-conjugate (Gadofluorine MÔ; Schering AG, Berlin, Germany) in a chemically induced tumor model of varying malignancy. Because of the tendency for this agent to form large micelles in water and to bind strongly to hydrophobic sites on proteins, it was hypothesized that patterns of dynamic tumor enhancement could be used to differentiate benign from malignant lesions, to grade the severity of malignancies and to define areas of tumor necrosis. Gadofluorine M, 0.05,mmol,Gd,kg,1, was administered intravenously to 28 anesthetized rats that had developed over 10 months mammary tumors of varying degrees of malignancy as a consequence of intraperitoneal administration of N -ethyl- N -nitrosourea (ENU), 45,250,mg,kg,1. These tumors ranged histologically from benign fibroadenomas to highly undifferentiated adenocarcinomas. Dynamic enhancement data were analyzed kinetically using a two-compartment tumor model to generate estimates of fractional plasma volume (fPV), apparent fractional extracellular volume (fEV*) and an endothelial transfer coefficient (KPS) for this contrast agent. Tumors were examined microscopically for tumor type, degree of malignancy (Scarff,Bloom,Richardson score) and location of necrosis. Eighteen tumor-bearing rats were successfully imaged. MRI data showed an immediate strong and gradually increasing tumor enhancement. KPS and fEV*, but not fPV obtained from tumors correlated significantly (p,<,0.05) with the SBR tumor grade, r,=,0.65 and 0.56, respectively. Estimates for KPS and fEV* but not fPV were significantly lower in a group consisting of benign and low-grade malignant tumors compared with the group of less-differentiated high-grade tumors (1.61,±,0.64 vs 3.37,±,1.49, p,<,0.01; 0.45,±,0.17 vs 0.78,±,0.24, p,<,0.01; and 0.076,±,0.048 vs 0.121,±,0.088, p,=,0.24, respectively). It is concluded that the protein-avid MRI contrast agent Gadofluorine M enhances tumors of varying malignancy depending on the tumor grade, higher contrast agent accumulation for more malignant lesions. The results show potential utility for differentiating benign and low-grade malignant lesions from high-grade cancers. Copyright © 2006 John Wiley & Sons, Ltd. [source] Thaliporphine protects ischemic and ischemic-reperfused rat hearts via an NO-dependent mechanismDRUG DEVELOPMENT RESEARCH, Issue 3 2001Li-Man Hung Abstract In ischemia or ischemia-reperfusion (I/R), nitric oxide (NO) can potentially exert several beneficial effects. Thaliporphine, a natural alkaloid with Ca2+ channel-activating and Na+/K+ channel-blocking activities, increased NO levels and exerted cardioprotective action in ischemic or I/R rats. The role of NO in the cardioprotective actions of thaliporphine was assessed. The severity of rhythm disturbances and mortality in anesthetized rats with either coronary artery occlusion for 30 min, or 5 min followed by 30-min reperfusion, were monitored and compared in thaliporphine- vs. placebo-treated groups. Thaliporphine treatment significantly increased NO and decreased lactate dehydrogenase (LDH) levels in the blood during the end period of ischemia or I/R. These changes in NO and LDH levels by thaliporphine were associated with a reduction in the incidence and duration of ventricular tachycardia (VT) and ventricular fibrillation (VF) during ischemic or I/R period. The mortality of animals was also completely prevented by 1 × 10,8 moles/kg of thaliporphine. In animals subjected to 4 h of left coronary artery occlusion, 1 × 10,7 moles/kg of thaliporphine dramatic reduced cardiac infarct zone from 46 ± 6% to 7.1 ± 1.9%. Inhibition of NO synthesis with 3.7 × 10,6 moles/kg of N, -nitro-L-arginine methyl ester (L-NAME) abolished the beneficial effects of thaliporphine during 30 min or 4 h myocardial ischemia. However, the antiarrhythmic activity and mortality reduction efficacy of thaliporphine during reperfusion after 5 min of ischemia was only partially antagonized by L-NAME. These results showed that thaliporphine efficiently exerted the cardioprotections either in acute or prolonged coronary artery occlusion or occlusion-reperfusion situations. The fact that thaliporphine induced cardioprotective effects were abrogated by L-NAME indicates that NO is an important mediator for the cardioprotective effects of thaliporphine in acute or prolonged ischemia, whereas antioxidant activities may contribute to the protection of I/R injury. Drug Dev. Res. 52:446,453, 2001. © 2001 Wiley-Liss, Inc. [source] Effects of Potassium Concentration on Firing Patterns of Low-Calcium Epileptiform Activity in Anesthetized Rat Hippocampus: Inducing of Persistent Spike ActivityEPILEPSIA, Issue 4 2006Zhouyan Feng Summary:,Purpose: It has been shown that a low-calcium high-potassium solution can generate ictal-like epileptiform activity in vitro and in vivo. Moreover, during status epileptiform activity, the concentration of [K+]o increases, and the concentration of [Ca2+]o decreases in brain tissue. Therefore we tested the hypothesis that long-lasting persistent spike activity, similar to one of the patterns of status epilepticus, could be generated by a high-potassium, low-calcium solution in the hippocampus in vivo. Methods: Artificial cerebrospinal fluid was perfused over the surface of the exposed left dorsal hippocampus of anesthetized rats. A stimulating electrode and a recording probe were placed in the CA1 region. Results: By elevating K+ concentration from 6 to 12 mM in the perfusate solution, the typical firing pattern of low-calcium ictal bursts was transformed into persistent spike activity in the CA1 region with synaptic transmission being suppressed by calcium chelator EGTA. The activity was characterized by double spikes repeated at a frequency ,4 Hz that could last for >1 h. The analysis of multiple unit activity showed that both elevating [K+]o and lowering [Ca2+]o decreased the inhibition period after the response of paired-pulse stimulation, indicating a suppression of the after-hyperpolarization (AHP) activity. Conclusions: These results suggest that persistent status epilepticus,like spike activity can be induced by nonsynaptic mechanisms when synaptic transmission is blocked. The unique double-spike pattern of this activity is presumably caused by higher K+ concentration augmenting the frequency of typical low-calcium nonsynaptic burst activity. [source] PRECLINICAL STUDY: FULL ARTICLE: Effects of fatty acid amide hydrolase inhibition on neuronal responses to nicotine, cocaine and morphine in the nucleus accumbens shell and ventral tegmental area: involvement of PPAR-, nuclear receptorsADDICTION BIOLOGY, Issue 3 2010Antonio Luchicchi ABSTRACT The endocannabinoid system regulates neurotransmission in brain regions relevant to neurobiological and behavioral actions of addicting drugs. We recently demonstrated that inhibition by URB597 of fatty acid amide hydrolase (FAAH), the main enzyme that degrades the endogenous cannabinoid N-acylethanolamine (NAE) anandamide and the endogenous non-cannabinoid NAEs oleoylethanolamide and palmitoylethanolamide, blocks nicotine-induced excitation of ventral tegmental area (VTA) dopamine (DA) neurons and DA release in the shell of the nucleus accumbens (ShNAc), as well as nicotine-induced drug self-administration, conditioned place preference and relapse in rats. Here, we studied whether effects of FAAH inhibition on nicotine-induced changes in activity of VTA DA neurons were specific for nicotine or extended to two drugs of abuse acting through different mechanisms, cocaine and morphine. We also evaluated whether FAAH inhibition affects nicotine-, cocaine- or morphine-induced actions in the ShNAc. Experiments involved single-unit electrophysiological recordings from DA neurons in the VTA and medium spiny neurons in the ShNAc in anesthetized rats. We found that URB597 blocked effects of nicotine and cocaine in the ShNAc through activation of both surface cannabinoid CB1-receptors and alpha-type peroxisome proliferator-activated nuclear receptor. URB597 did not alter the effects of either cocaine or morphine on VTA DA neurons. These results show that the blockade of nicotine-induced excitation of VTA DA neurons, which we previously described, is selective for nicotine and indicate novel mechanisms recruited to regulate the effects of addicting drugs within the ShNAc of the brain reward system. [source] In vivo voltammetric monitoring of norepinephrine release in the rat ventral bed nucleus of the stria terminalis and anteroventral thalamic nucleusEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2009Jinwoo Park Abstract The role and contribution of the dense noradrenergic innervation in the ventral bed nucleus of the stria terminalis (vBNST) and anteroventral thalamic nucleus (AV) to biological function and animal behaviors is poorly understood due to the small size of these nuclei. The aim of this study was to compare norepinephrine release and uptake in the vBNST with that in the AV of anesthetized rats. Measurements were made in vivo with fast-scan cyclic voltammetry following electrical stimulation of noradrenergic projection pathways, either the dorsal noradrenergic bundle (DNB) or the ventral noradrenergic bundle (VNB). The substance detected was identified as norepinephrine based upon voltammetric, anatomical, neurochemical and pharmacological evidence. Fast-scan cyclic voltammetry enables the selective monitoring of local norepinephrine overflow in the vBNST evoked by the stimulation of either the DNB or the VNB while norepinephrine in the AV was only evoked by DNB stimulation. The ,2-adrenoceptor antagonist yohimbine and the norepinephrine uptake inhibitor desipramine increased norepinephrine overflow and slowed its disappearance in both regions. However, control of extracellular norepinephrine by both autoreceptors and uptake was greater in the AV. The greater control exerted by autoreceptors and uptake in the AV resulted in reduced extracellular concentration compared with the v,BNST when large numbers of stimulation pulses were employed. The differences in noradrenergic transmission observed in the terminal fields of the v,BNST and the AV may differentially regulate activity in these two regions that both contain high densities of norepinephrine terminals. [source] Tactile responses of hindpaw, forepaw and whisker neurons in the thalamic ventrobasal complex of anesthetized ratsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2008J. Aguilar Abstract The majority of studies investigating responses of thalamocortical neurons to tactile stimuli have focused on the whisker representation of the rat thalamus: the ventral,posterior,medial nucleus (VPM). To test whether the basic properties of thalamocortical responses to tactile stimuli could be extended to the entire ventrobasal complex, we recorded single neurons from the whisker, forepaw and hindpaw thalamic representations. We performed a systematic analysis of responses to stereotyped tactile stimuli , 500 ms pulses (i.e. ON,OFF stimuli) or 1 ms pulses (i.e. impulsive stimuli) , under two different anesthetics (pentobarbital or urethane). We obtained the following main results: (i) the tuning of cells to ON vs. OFF stimuli displayed a gradient across neurons, so that two-thirds of cells responded more to ON stimuli and one-third responded more to OFF stimuli; (ii) on average, response magnitudes did not differ between ON and OFF stimuli, whereas latencies of response to OFF stimuli were a few milliseconds longer; (iii) latencies of response to ON and OFF stimuli were highly correlated; (iv) responses to impulsive stimuli and ON stimuli showed a strong correlation, whereas the relationship between the responses to impulsive stimuli and OFF stimuli was subtler; (v) unlike ON responses, OFF responses did not decrease when stimuli were moved from the receptive field center to a close location in the excitatory surround. We obtained the same results for hindpaw, forepaw and whisker neurons. Our results support the view of a neurophysiologically homogeneous ventrobasal complex, in which OFF responses participate in the structure of the spatiotemporal receptive field of thalamocortical neurons for tactile stimuli. [source] Rapid assessment of in vivo cholinergic transmission by amperometric detection of changes in extracellular choline levelsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2004Vinay Parikh Abstract Conventional microdialysis methods for measuring acetylcholine (ACh) efflux do not provide sufficient temporal resolution to relate cholinergic transmission to individual stimuli or behavioral responses, or sufficient spatial resolution to investigate heterogeneities in such regulation within a brain region. In an effort to overcome these constraints, we investigated a ceramic-based microelectrode array designed to measure amperometrically rapid changes in extracellular choline as a marker for cholinergic transmission in the frontoparietal cortex of anesthetized rats. These microelectrodes exhibited detection limits of 300 nm for choline and selectivity (> 100 : 1) of choline over interferents such as ascorbic acid. Intracortical pressure ejections of choline (20 mm, 66,400 nL) and ACh (10 and 100 mm, 200 nL) dose-dependently increased choline-related signals that were cleared to background levels within 10 s. ACh, but not choline-induced signals, were significantly attenuated by co-ejection of the acetylcholinesterase inhibitor neostigmine (Neo; 100 mm). Pressure ejections of drugs known to increase cortical ACh efflux, potassium (KCl; 70 mm, 66, 200 nL) and scopolamine (Scop; 10 mm, 200 nL), also markedly increased extracellular choline signals, which again were inhibited by Neo. Scop-induced choline signals were also found to be tetrodotoxin-sensitive. Collectively, these findings suggest that drug-induced increases in current measured with these microelectrode arrays reflect the oxidation of choline that is neuronally derived from the release and subsequent hydrolysis of ACh. Choline signals assessed using enzyme-selective microelectrode arrays may represent a rapid, sensitive and spatially discrete measure of cholinergic transmission. [source] Effects of melatonin and caffeic acid phenethyl ester on testicular injury induced by myocardial ischemia/reperfusion in ratsFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 3 2005Mukaddes E Abstract Experimental studies indicate that ischemia/reperfusion (I/R) causes remote organ injury although the molecular mechanism has not been clearly defined. In this report, the role of oxidative injury on testicular damage following myocardial I/R injury and the effects of antioxidant agents, melatonin and caffeic acid phenethyl ester (CAPE), on testicular injury were investigated. As far as we know, this is the first report demonstrating that myocardial I/R induces damage to the testes. Thirty-two male Wistar rats were randomly divided into four groups: sham operation (SO), I/R + vehicle, I/R + melatonin, and I/R + caffeic acid phenethyl ester. To produce cardiac damage, the left main coronary artery was occluded for 30 min, followed by 120 min reperfusion, in anesthetized rats. Serum nitric oxide (NO) and malondialdehyde (MDA) levels and morphological changes were examined. I/R was accompanied by a significant increase in serum MDA and NO levels, whereas, melatonin and CAPE administration significantly reduced these values. Melatonin was more efficient in reducing MDA levels than CAPE (P < 0.05). I/R induced myocardial damage, manifested as the histopathological evidence of intracellular vacuolization, interstitial edema, neutrophil infiltration and coagulative necrosis. I/R + vehicle group showed many histological alterations such as focal tubular atrophy, and degeneration and disorganization of the seminiferous epithelium in testes. The number of atrophic tubules and degenerating cells was significantly higher in I/R + vehicle group than that of SO group. Melatonin and CAPE significantly reduced the number of degenerating cells; additionally, melatonin reduced the number of atrophic tubules (P < 0.05). Our results indicate that myocardial I/R induces severe testicular damage and antioxidant agents, especially melatonin, have protective effects on testicular injury after myocardial I/R. Our data emphasize that oxygen-based reactants may play a central role in remote organ injury. [source] Hippocampal synaptic transmission and LTP in vivo are intact following bilateral vestibular deafferentation in the ratHIPPOCAMPUS, Issue 4 2010Yiwen Zheng Abstract Numerous studies in animals and humans have shown that damage to the vestibular system in the inner ear results in spatial memory deficits, presumably because areas of the brain such as the hippocampus require vestibular input to accurately represent the spatial environment. Consistent with this hypothesis, studies in animals have demonstrated that complete bilateral vestibular deafferentation (BVD) causes a disruption of place cell firing as well as theta activity. The aim of this study was to investigate whether BVD in rats affects baseline field potentials (field excitatory postsynaptic potentials and population spikes) and long-term potentiation (LTP) in CA1 and the dentate gyrus (DG) of awake freely moving rats up to 43 days post-BVD and of anesthetized rats at 7 months post-BVD. Compared to sham controls, BVD had no significant effect on either baseline field potentials or LTP in either condition. These results suggest that although BVD interferes with the encoding, consolidation, and/or retrieval of spatial memories and the function of place cells, these changes are not related to detectable in vivo decrements in basal synaptic transmission or LTP, at least in the investigated pathways. © 2009 Wiley-Liss, Inc. [source] Frontal cortical afferents facilitate striatal nitric oxide transmission in vivo via a NMDA receptor and neuronal NOS-dependent mechanismJOURNAL OF NEUROCHEMISTRY, Issue 3 2007Stephen Sammut Abstract Striatal nitric oxide (NO) signaling plays a critical role in modulating neural processing and motor behavior. Nitrergic interneurons receive synaptic inputs from corticostriatal neurons and are activated via ionotropic glutamate receptor stimulation. However, the afferent regulation of NO signaling is poorly characterized. The role of frontal cortical afferents in regulating NO transmission was assessed in anesthetized rats using amperometric microsensor measurements of NO efflux and local field potential recordings. Low frequency (3 Hz) electrical stimulation of the ipsilateral cortex did not consistently evoke detectable changes in striatal NO efflux. In contrast, train stimulation (30 Hz) of frontal cortical afferents facilitated NO efflux in a stimulus intensity-dependent manner. Nitric oxide efflux evoked by train stimulation was transient, reproducible over time, and attenuated by systemic administration of either the NMDA receptor antagonist MK-801 or the neuronal NO synthase inhibitors 7-nitroindazole and NG -propyl- l -arginine. The interaction between NO efflux evoked via train stimulation and local striatal neuron activity was assessed using dual microsensor and local field potential recordings carried out concurrently in the contralateral and ipsilateral striatum, respectively. Systemic administration of the non-specific NO synthase inhibitor methylene blue attenuated both evoked NO efflux and the peak oscillation frequency (within the delta band) of local field potentials recorded immediately after train stimulation. Taken together, these observations indicate that feed-forward activation of neuronal NO signaling by phasic activation of frontal cortical afferents facilitates the synchronization of glutamate driven oscillations in striatal neurons. Thus, NO signaling may act to amplify coherent corticostriatal transmission and synchronize striatal output. [source] Chronic Morphine Treatment and Withdrawal Increase Extracellular Levels of Norepinephrine in the Rat Bed Nucleus of the Stria TerminalisJOURNAL OF NEUROCHEMISTRY, Issue 2 2000José Antonio Fuentealba Extracellular levels of norepinephrine (NE) and glutamate (Glu) in the ventral bed nucleus of the stria terminalis (vBNST) of saline- and chronic morphine-treated rats, with or without withdrawal, were studied by means of the in vivo microdialysis technique in anesthetized rats. In addition, the tissue concentration of NE was studied at different rostrocaudal levels of the vBNST. Chronic morphine treatment significantly increased extracellular levels of NE, but not Glu, in vBNST. At 48 h after naloxone-induced morphine withdrawal there was a further significant increase in the extracellular levels of NE, but not Glu, in vBNST. The presence of UK 14304, an ,2 -adrenergic agonist, induced a significant decrease in NE extracellular levels in all experimental groups. In contrast, UK 14304 induced a significant decrease in Glu extracellular levels only in saline-treated rats. The results also show that the vBNST presents a rostrocaudal gradient of NE and contains 9.4% of total brain NE. The increase in NE extracellular levels in vBNST induced by chronic morphine treatment and the further increase in NE levels 48 h after naloxone-induced morphine withdrawal suggest that NE in vBNST may be involved in the pharmacological effects of chronic morphine and withdrawal. [source] Differential localization of carbachol- and bicuculline-sensitive pontine sites for eliciting REM sleep-like effects in anesthetized ratsJOURNAL OF SLEEP RESEARCH, Issue 1 2009VICTOR B. FENIK Summary Carbachol, a cholinergic agonist, and GABAA receptor antagonists injected into the pontine dorsomedial reticular formation can trigger rapid eye movement (REM) sleep-like state. Data suggest that GABAergic and cholinergic effects interact to produce this effect but the sites where this occurs have not been delineated. In urethane-anesthetized rats, in which carbachol effectively elicits REM sleep-like episodes (REMSLE), we tested the ability of 10 nL microinjections of carbachol (10 mm) and bicuculline (0.5 or 2 mm) to elicit REMSLE at 47 sites located within the dorsal pontine reticular formation at the levels -8.00 to -10.80 from bregma (B) (Paxinos and Watson, The Rat Brain in Stereotaxic Coordinates, Academic Press, San Diego, 1997). At rostral levels, most carbachol and some bicuculline injections elicited REMSLE with latencies that gradually decreased from 242 to 12 s for carbachol and from 908 to 38 s for bicuculline for more caudal injection sites. As the latencies decreased, the durations of bicuculline-elicited REMSLE increased from 104 s to over 38 min, and the effect was dose dependent, whereas the duration of carbachol-elicited REMSLE changed little (104,354 s). Plots of REMSLE latency versus the antero-posterior coordinates revealed that both drugs were maximally effective near B-8.80. At levels caudal to B-8.80, carbachol was effective at few sites, whereas bicuculline-elicited REMSLE to at least B-9.30 level. Thus, the bicuculline-sensitive sites extended further caudally than those for carbachol and antagonism of GABAA receptors both triggered REMSLE and controlled their duration, whereas carbachol effects on REMSLE duration were small or limited by its concurrent REMSLE-opposing actions. [source] Neuropathological changes in vibration injury: An experimental studyMICROSURGERY, Issue 1 2005Hani S. Matloub M.D. Vibration syndrome, a clinical condition arising from chronic use of vibrating tools, is associated with a spectrum of neurovascular symptoms. To date, only its vascular pathology has been extensively studied; we sought to determine what direct neurologic injury, if any, is caused by vibration. Hindlimbs of anesthetized rats were affixed to a vibrating platform 4 h a day for 7 days. Study animals were vibrated with set parameters for frequency, acceleration, velocity, and amplitude; control animals were not vibrated. On day 7, nerves were studied by light and electron microscopy. While light microscopy showed minimal histologic differences between vibrated (n = 12) and control (n = 12) nerves, electron microscopic changes were dramatic. Splitting of the myelin sheath and axonal damage (e.g., myelin balls and "finger ring") were consistently seen in both myelinated and nonmyelinated axons. Despite relatively short vibration, definite pathology was demonstrated, suggesting that vibration syndrome has a direct neurologic component. © 2005 Wiley-Liss, Inc. Microsurgery 25:71,75, 2005. [source] Sensory nerve conduction deficit in experimental monoclonal gammopathy of undetermined significance (MGUS) neuropathyMUSCLE AND NERVE, Issue 6 2001Michael W. Lawlor BS Abstract An emerging body of evidence from in vitro studies and in vivo animal models supports a pathogenic role of antibodies in the development of peripheral neuropathy associated with monoclonal gammopathy of undetermined significance (MGUS). Although the assessment of motor and sensory nerve fiber function is of clinical importance, it is seldom applied experimentally. We describe the application of an electrophysiologic method for the evaluation of motor and sensory nerve fiber function using an experimental model of MGUS neuropathy. Supramaximal stimulation of the tibial nerve elicited an early motor response (M-wave, 1.7 ± 0.1 ms, n = 10) and a late sensory (H-reflex, 7.8 ± 0.1 ms, n = 10) response that was recorded from the hind foot of anesthetized rats. Intraneural injection of serum antibodies from a MGUS patient with sensorimotor polyneuropathy, but not from an age-matched control subject, produced a marked attenuation of the H-reflex (P < 0.01, n = 10) without affecting the M-wave. Light and electron microscopy of affected nerve showed myelinoaxonal degeneration with sparing of the smaller unmyelinated nerve fibers. The combined electrophysiologic and morphologic findings presented in this study are consistent with a selective sensory conduction deficit in MGUS neuropathy. Selective injury of afferent nerve fibers by this patient's serum antibodies may result from reactivity to neural antigens uniquely expressed by sensory neurons. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 809,816, 2001 [source] Baseline physiological state and the fMRI-BOLD signal response to apnea in anesthetized ratsNMR IN BIOMEDICINE, Issue 5 2003Sridhar S. Kannurpatti Abstract To decipher the biophysical mechanism behind the fMRI-BOLD response to apnea and its dependence on the baseline cerebral blood flow and oxygenation, fMRI and laser Doppler flow (LDF) studies were carried out in anesthetized rats. Baseline cerebral blood flow (CBF) and PaO2 were modulated by ventilating with different gas mixtures namely, room air (21% O2), 100% O2, carbogen (95% O2+5% CO2), 2% CO2 in air or 5% CO2 in air, respectively. A decrease in BOLD signal intensity was observed after the onset of apnea with either room air, 2% CO2 or 5% CO2 ventilation. PaO2 and cerebral tissue PO2 decreased during apnea under these conditions. However, the apnea-induced BOLD signal intensity was unaffected with carbogen ventilation and increased with 100% O2 ventilation, during which PaO2 remained constant and cerebral tissue PO2 increased. When baseline CBF was high during hypercapnia, a faster decrease occurred in the apnea-induced BOLD signal. Apnea induced the largest increase in CBF of 85±25% when ventilated with 2% CO2 while a 44±8% increase was observed with room air. During the other ventilatory conditions, minimal or no significant change in CBF was observed during apnea. These results show a significant correlation between the BOLD signal change and tissue PO2 in response to apnea under different physiological conditions. Apnea-induced increase in CBF affects the magnitude of the BOLD signal response when PaO2 remains constant or changes minimally. Copyright © 2001 John Wiley & Sons, Ltd. [source] Ventromedial medulla: Pain modulation and beyondTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 1 2005Peggy Mason Abstract The midbrain periaqueductal gray (PAG) and ventromedial medulla (VMM) are generally viewed as the core of an endogenous descending modulatory system. However, available data demonstrate that PAG and VMM do not specifically target nociceptive transmission and that activation of either structure affects numerous homeostatic physiological processes. Pseudorabies virus (PRV) is a useful tracer that is retrogradely and transynaptically transported. PRV injections into homeostatic effector organs invariably label VMM neurons, both serotonergic and nonserotonergic. Studies in anesthetized rats have implicated two types of nonserotonergic VMM neurons in nociceptive modulation: ON cells are thought to facilitate nociception and OFF cells to inhibit nociception. Yet, in the unanesthetized animal, the discharge of VMM neurons changes in response to innocuous stimuli and during situations unrelated to nociception. In particular, VMM cells appear to modulate the timing of micturition, with ON cells promoting the initiation of voiding and OFF cells promoting urine storage. VMM cells also modulate sensory transmission. During both micturition and sleep, OFF cells discharge and sensory responsiveness is depressed. In sum, the VMM is hypothesized to modulate spinal sensory, autonomic, and motor circuits in order to maintain homeostasis. J. Comp. Neurol. 493:2,8, 2005. © 2005 Wiley-Liss, Inc. [source] In vivo electroporation and ubiquitin promoter , a protocol for sustained gene expression in the lungTHE JOURNAL OF GENE MEDICINE, Issue 7 2006Amiq Gazdhar Abstract Background Gene therapy applications require safe and efficient methods for gene transfer. Present methods are restricted by low efficiency and short duration of transgene expression. In vivo electroporation, a physical method of gene transfer, has evolved as an efficient method in recent years. We present a protocol involving electroporation combined with a long-acting promoter system for gene transfer to the lung. Methods The study was designed to evaluate electroporation-mediated gene transfer to the lung and to analyze a promoter system that allows prolonged transgene expression. A volume of 250 µl of purified plasmid DNA suspended in water was instilled into the left lung of anesthetized rats, followed by left thoracotomy and electroporation of the exposed left lung. Plasmids pCiKlux and pUblux expressing luciferase under the control of the cytomegalovirus immediate-early promoter/enhancer (CMV-IEPE) or human polyubiquitin c (Ubc) promoter were used. Electroporation conditions were optimized with four pulses (200 V/cm, 20 ms at 1 Hz) using flat plate electrodes. The animals were sacrificed at different time points up to day 40, after gene transfer. Gene expression was detected and quantified by bioluminescent reporter imaging (BLI) and relative light units per milligram of protein (RLU/mg) was measured by luminometer for p.Pyralis luciferase and immunohistochemistry, using an anti-luciferase antibody. Results Gene expression with the CMV-IEPE promoter was highest 24 h after gene transfer (2932 ± 249.4 relative light units (RLU)/mg of total lung protein) and returned to baseline by day 3 (382 ± 318 RLU/mg of total lung protein); at day 5 no expression was detected, whereas gene expression under the Ubc promoter was detected up to day 40 (1989 ± 710 RLU/mg of total lung protein) with a peak at day 20 (2821 ± 2092 RLU/mg of total lung protein). Arterial blood gas (PaO2), histological assessment and cytokine measurements showed no significant toxicity neither at day 1 nor at day 40. Conclusions These results provide evidence that in vivo electroporation is a safe and effective tool for non-viral gene delivery to the lungs. If this method is used in combination with a long-acting promoter system, sustained transgene expression can be achieved. Copyright © 2006 John Wiley & Sons, Ltd. [source] Erectile Function in Two-Kidney, One-Clip Hypertensive Rats is Maintained by a Potential Increase in Nitric Oxide ProductionTHE JOURNAL OF SEXUAL MEDICINE, Issue S3 2009A. Elizabeth Linder PhD ABSTRACT Introduction., Hypertension is closely associated with erectile dysfunction (ED) as it has been observed in many experimental models of hypertension. Additionally, epidemiological studies show that approximately a third of hypertensive patients have ED. Aim., To test the hypothesis that the two-kidney, one-clip (2K-1C) rat model of hypertension displays normal erectile function due to increased nitric oxide (NO) production in the penis. Methods., Ganglionic-induced increase in intracavernosal pressure (ICP)/mean arterial pressure (MAP) ratio was used as an index of erectile function in 2K-1C and in normotensive sham-operated (SHAM) anesthetized rats. Cavernosal strips from hypertensive and normotensive rats were used for isometric tension measurement. The contraction induced by alpha-adrenergic agonist phenylephrine and the relaxation induced by the NO donor sodium nitroprusside (SNP) and by the Rho-kinase inhibitor Y-27632 were performed in the absence and in the presence of the NO synthase inhibitor N, -nitro-L-arginine (L-NNA). Results., Changes in ICP/MAP induced by ganglionic stimulation were not different between 2K-1C and SHAM rats. The contractile response induced by phenylephrine as well as the relaxation induced by SNP or the Y-27632 were similar in cavernosal strips from both groups. However, in the presence of L-NNA, the relaxation induced by Y-27632 was significantly impaired in 2K-1C compared to SHAM. Conclusions., These data suggest that hypertension and ED could be dissociated from high levels of blood pressure in some animal models of hypertension. Erectile function in 2K-1C hypertensive rats is maintained in spite of the increased Rho-kinase activity by increased NO signaling. Linder AE, Dorrance AM, Mills TM, Webb RC, and Leite R. Erectile function in two-kidney, one-clip hypertensive rats is maintained by a potential increase in nitric oxide production. J Sex Med 2009;6(suppl 3):279,285. [source] Role of the Neurokinin-1 Receptors in Ejaculation in Anesthetized RatsTHE JOURNAL OF SEXUAL MEDICINE, Issue 1 2009Pierre Clement PhD ABSTRACT Introduction., Several lines of evidence indicate a role for substance P in the control of ejaculation, although its mode of action needs to be clarified. Aim., The effects and sites of action of a selective antagonist for the substance P-preferred receptor (neurokinin-1 receptor subtype; NK1) were investigated in a pharmacological model of ejaculation. Methods., Ejaculation was induced in anesthetized rats by intracerebroventricular (icv) delivery of the dopamine D3 receptor preferring agonist 7-hydroxy-2-(di-N-propylamino)tetralin (7-OH-DPAT). The effects of the selective NK1 antagonist RP67580 on 7-OH-DPAT-induced ejaculation were measured following intraperitoneal (ip), icv, or intrathecal (it) (third lumbar spinal segment; L3) administration. Main Outcome Measures., Intraseminal vesicle pressure (SVP) and electromyogram of the bulbospongiosus muscle (BS) were recorded as physiological markers of emission and expulsion phases of ejaculation, respectively. Results., Upon ip, icv, or it administration, RP67580 significantly reduced the occurrence of ejaculation elicited by 7-OH-DPAT. A mild decrease in the occurrence of SVP and BS responses was observed in rats treated ip with RP67580, whereas only SVP responses were moderately affected following icv or it administration. Conclusion., These results show the multilevel regulation of 7-OH-DPAT-induced ejaculation by NK1 receptors. Clement P, Peeters M, Bernabe J, Laurin M, Alexandre L, and Giuliano F. Role of the neurokinin-1 receptors in ejaculation in anesthetized rats. J Sex Med 2009;6:126,134. [source] Effects of Insulin-Like Growth Factor-1 Gene Transfer on Myosin Heavy Chains in Denervated Rat Laryngeal Muscle,THE LARYNGOSCOPE, Issue 2 2004Paul W. Flint MD Abstract Objectives/Hypothesis: To determine whether the myotrophic activity of human insulin-like growth factor (hIGF)-1 promotes restoration of normal myosin heavy chain (MHC) composition after nerve injury, MHC composition was analyzed after hIGF-1 gene transfer in denervated rat laryngeal muscle. Study Design: Animal model to study effects of gene transfer on laryngeal paralysis. Methods: In anesthetized rats, the left recurrent and superior laryngeal nerves are cut and suture ligated. A midline thyrotomy is performed, and the thyroarytenoid muscle is injected with a polyvinyl-based formulation containing a muscle specific expression system and hIGF-1 DNA (treatment group) or saline (control group). After 30 days, animals were killed, and the thyroarytenoid muscle was removed and processed for sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDSPAGE). Densitometric measurements were obtained to determine composition of MHCs. Results: As previously described, MHC composition in denervated laryngeal muscle was characterized by a decrease in type IIB and IIL and up-regulation of IIA/IIX. Compared with controls, hIGF-1 treated animals demonstrated a significant increase in expression of type IIB and IIL and a significant decrease in expression of type IIA/X. Conclusions: These findings suggest that the myotrophic effect of hIGF-1 gene transfer results in normalization of MHC composition in denervated muscle, with suppression of type IIA/X MHC and promotion of type IIL expression. [source] Evidence that endogenous inosine and adenosine-mediated hyperglycaemia during ischaemia,reperfusion through A3 adenosine receptorsAUTONOMIC & AUTACOID PHARMACOLOGY, Issue 4 2009D. Cortés Summary 1,The molecular mechanism underlying stress-induced hyperglycemia has not been comprehensively clarified. Recently, we demonstrated in ischaemia-reperfusion (I-R) stress-subjected liver that inosine and adenosine are mainly responsible for the hyperglycemia observed. 2,We aimed to advance in the knowledge of the role of inosine plus adenosine as mediators of hepatic-induced hyperglycemia detected after I-R in lower limbs. 3,Acute ischaemia was conducted in anesthetized rats by occluding downstream abdominal aorta and cava vein; then, reperfusion was allowed. Blood samples from hepatic or abdominal cava veins were taken throughout the experiments to measure glucose, inosine and adenosine. Antagonists to adenosine (AdoR) and adrenergic receptors (AdrR) were administered during ischaemia to analyze their effect on hepatic glucose release. 4,Ischaemia up to 60 min produced minor increase of glucose and nucleosides blood values, but 5 min of ischaemia followed by 2- (or 10-) min reperfusion increased glucose 23%, and those of inosine or adenosine by 100%. After 60 min of ischaemia and 10 min of reperfusion, glycemia rose 2-fold and blood inosine and adenosine, 3.3- and 2.7-fold, respectively. A linear positive correlation, r2, as high as 0.839 between glucose and either nucleoside blood values was calculated. The hyperglycemia response to I-R decreased by 0, 25, 33, 45 and 100% after selective inhibition of A2B AdoR, A2A AdoR, a1B AdrR, A1 AdoR, and A3 AdoR, respectively. 5,Inosine-adenosine couple through activation of hepatic A3 AdoR is the main signal for releasing glucose from liver glycogen and for promoting hyperglycemia following experimental injury of I-R from lower limbs. [source] Biliary clearance of bromosulfophthalein in anesthetized and freely moving conscious ratBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 2 2009Ju-Hee Oh Abstract The aim of this study was to investigate the effect of anesthesia on the pharmacokinetics of bromosulfophthalein (BSP) with focus on biliary clearance. The plasma concentration profile and biliary clearance of intravenously administered BSP was compared in conscious freely moving bile duct catheterized rats and rats anesthetized with ketamine or Zoletil. The plasma concentration of BSP in conscious rats was similar to that of anesthetized rats, irrespective of the anesthetic used. There was no significant difference in the volume of distribution, total body clearance and mean residence time of BSP between the groups. The biliary clearance of BSP in rats anesthetized using ketamine or Zoletil was also similar to that of conscious rats. Only bile flow was increased under anesthetization compared with conscious rats. These results demonstrate that the pharmacokinetics of BSP, including biliary clearance, in ketamine or Zoletil anesthetized rats is virtually identical to that in conscious rats and it may be related to blood flow limited hepatic disposition of BSP. Furthermore, they suggest the conscious rat model does not offer methodological advantage and the anesthesia model is suitable for a realistic approximation of the hepatobiliary transport of BSP. Copyright © 2009 John Wiley & Sons, Ltd. [source] Arterial spin labeling demonstrates that focal amygdalar glutamatergic agonist infusion leads to rapid diffuse cerebral activationACTA NEUROLOGICA SCANDINAVICA, Issue 3 2010J. P. Munasinghe Munasinghe JP, Banerjee M, Acosta MT, Banks M, Heffer A, Silva AC, Koretsky A, Theodore WH. Arterial spin labeling demonstrates that focal amygdalar glutamatergic agonist infusion leads to rapid diffuse cerebral activation. Acta Neurol Scand: 2010: 121: 209,216. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objectives,,, To investigate acute effects of intra-amygdalar excitatory amino acid administration on blood flow, relaxation time and apparent diffusion coefficient in rat brain. Materials and methods,,, Several days after MR-compatible cannula placement in right basolateral amygdala, anesthetized rats were imaged at 7 T. Relative cerebral blood flow (CBF) was measured before and 60 min after infusion of 10 nmol KA, cAMPA, ATPA, or normal saline using arterial spin labeling. Quantitative T2 and diffusion-weighted images were acquired. rCBF, T2 and ADC values were evaluated in bilateral basolateral amygdala, hippocampus, basal ganglia, frontal and parietal regions. Results,,, KA led to the highest, and ATPA lowest bilateral rCBF increases. Time courses varied among drugs. T2 for KA and AMPA was higher while ADC was lower for KA. Conclusions,,, Intra-amygdalar injection of GluR agonists evoked bilateral seizure activity and increased rCBF, greater for KA and AMPA than selective ATPA GluR5 activation. [source] | |||||||||||||||||||||||||