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Anandamide
Kinds of Anandamide Selected AbstractsAnandamide regulates neuropeptide release from capsaicin-sensitive primary sensory neurons by activating both the cannabinoid 1 receptor and the vanilloid receptor 1 in vitroEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2003Jatinder Ahluwalia Abstract The effect of anandamide, which activates both the cannabinoid 1 (CB1) receptor and the vanilloid receptor 1 (VR1), was studied on calcitonin gene-related peptide (CGRP) release from cultured primary sensory neurons, the majority of which coexpress the CB1 receptor and VR1. Concentrations of anandamide <,1 µm produced a small but significant CB1 receptor-mediated inhibition of basal CGRP release while higher concentrations induced VR1-mediated CGRP release. The excitatory effect of anandamide was potentiated by the CB1 receptor antagonist SR141716A. In the presence of SR141716A at concentrations <,100 nm, anandamide was equipotent with capsaicin in stimulating CGRP release. However, at higher concentrations anandamide produced more CGRP release than equimolar concentrations of capsaicin. Three and ten nanomolar anandamide inhibited the capsaicin-evoked CGRP release. In the presence of SR141716A, treatments which activated protein kinase A, protein kinase C and phospholipase C significantly potentiated the anandamide-evoked CGRP release at all anandamide concentrations. Although this potentiation was reduced when the CB1 receptor antagonist was omitted from the buffer, the CGRP release evoked by 300 nm and 1 µm anandamide was still significantly larger than that seen with nonpotentiated cells. These data indicate that anandamide may regulate CGRP release from capsaicin-sensitive primary sensory neurons in vivo, and that the net effect of anandamide on transmitter release from capsaicin-sensitive primary sensory neurons depends on the concentration of anandamide and the state of the CB1 receptor and VR1. These findings also suggest that anandamide could be one of the molecules responsible for the development of inflammatory heat hyperalgesia. [source] Increased serum anandamide level at ruptured plaque site in patients with acute myocardial infarctionFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 3 2009Naotaka Maeda Abstract Inflammation caused by activated macrophages and T lymphocytes may trigger plaque rapture in acute coronary syndrome (ACS). Anandamide and 2-arachidonylglycerol (2-AG) are macrophage-derived signal lipids and may be involved in the pathogenesis of ACS, but no clinical relevant data have been reported. In 43 acute myocardial infarction (AMI) patients (66 ± 2 years), blood samples were obtained from the aortic root and the infarct-related coronary artery (IRA) using a PercuSurge system during primary percutaneous coronary intervention (PCI). In six patients with stable effort angina (SEA) (56 ± 6 years), blood samples were obtained from the site of stenosis during elective PCI. In 25 of the 43 AMI patients, anandamide was detected in the serum. Serum anandamide level was 35 ± 20 pmol/mL in the aorta and was significantly increased to 401 ± 134 pmol/mL in the IRA (P < 0.01). 2-AG was undetectable in most of the patients. In patients with SEA, neither anandamide nor 2-AG was detected in the serum at the plaque site. In AMI patients with anandamide detected, left ventricular ejection fraction at 2 weeks after PCI was increased by 3.7 ± 2.1% compared with that at the acute phase, while it was decreased by 3.0 ± 1.8% in those without anandamide detected (P < 0.05). The serum anandamide level at the culprit lesion was elevated compared with the systemic level in a significant number of AMI patients, indicating the synthesis of anandamide at the IRA. Anandamide was suggested to be derived from ruptured plaque and may exert beneficial effects in humans. [source] Anandamide enhances IL-10 production in activated microglia by targeting CB2 receptors: Roles of ERK1/2, JNK, and NF-,BGLIA, Issue 2 2010Fernando Correa Abstract The endocannabinoid system exhibits anti-inflammatory properties by regulating cytokine production. Anandamide (AEA) down-regulates proinflammatory cytokines in a viral model of multiple sclerosis (MS). However, little is known about the mechanisms by which AEA exerts these effects. Microglial cells are the main source of cytokines within the brain and the first barrier of defense against pathogens by acting as antigen presenting cells. IL-10 is a key physiological negative regulator of microglial activation. In this study we show that AEA enhances LPS/IFN,-induced IL-10 production in microglia by targeting CB2 receptors through the activation of ERK1/2 and JNK MAPKs. AEA also inhibits NF-,B activation by interfering with the phosphorylation of I,B,, which may result in an increase of IL-10 production. Moreover, endogenously produced IL-10 negatively regulates IL-12 and IL-23 cytokines, which in its turn modify the pattern of expression of transcription factorsinvolved in Th commitment of splenocytes. This suggeststhat by altering the cytokine network, AEA could indirectly modify the type of immune responses within the central nervous system (CNS). Accordingly, pharmacological modulation of AEA uptake and degradation might be a useful tool for treating neuroinflammatory diseases. © 2009 Wiley-Liss, Inc. [source] Anandamide administration alone and after inhibition of fatty acid amide hydrolase (FAAH) increases dopamine levels in the nucleus accumbens shell in ratsJOURNAL OF NEUROCHEMISTRY, Issue 2 2006Marcello Solinas Abstract Although endogenous cannabinoid systems have been implicated in the modulation of the rewarding effects of abused drugs and food, little is known about the direct effects of endogenous ligands for cannabinoid receptors on brain reward processes. Here we show for the first time that the intravenous administration of anandamide, an endogenous ligand for cannabinoid receptors, and its longer-lasting synthetic analog methanandamide, increase the extracellular dopamine levels in the nucleus accumbens shell of awake, freely moving rats, an effect characteristic of most drugs abused by humans. Anandamide produced two distinctly different effects on dopamine levels: (1) a rapid, transient increase that was blocked by the cannabinoid CB1 receptor antagonist rimonabant, but not by the vanilloid VR1 receptor antagonist capsazepine, and was magnified and prolonged by the fatty acid amide hydrolase (FAAH) enzyme inhibitor, URB597; (2) a smaller delayed and long-lasting increase, not sensitive to CB1, VR1 or FAAH blockade. Both effects were blocked by infusing either tetrodotoxin (TTX, 1 µm) or calcium-free Ringer's solution through the microdialysis probe, demonstrating that they were dependent on the physiologic activation of dopaminergic neurotransmission. Thus, these results indicate that anandamide, through the activation of the mesolimbic dopaminergic system, participates in the signaling of brain reward processes. [source] Gas chromatography,mass spectrometry analysis of endogenous cannabinoids in healthy and tumoral human brain and human cells in cultureJOURNAL OF NEUROCHEMISTRY, Issue 2 2001Mauro Maccarrone Endocannabinoids are lipid mediators thought to modulate central and peripheral neural functions. We report here gas chromatography,electron impact mass spectrometry analysis of human brain, showing that lipid extracts contain anandamide and 2-arachidonoylglycerol (2-AG), the most active endocannabinoids known to date. Human brain also contained the endocannabinoid-like compounds N -oleoylethanolamine, N -palmitoylethanolamine and N -stearoylethanolamine. Anandamide and 2-AG (0.16 ± 0.05 and 0.10 ± 0.05 nmol/mg protein, respectively) represented 7.7% and 4.8% of total endocannabinoid-like compounds, respectively. N -Palmitoyethanolamine was the most abundant (50%), followed by N -oleoyl (23.6%) and N -stearoyl (13.9%) ethanolamines. A similar composition in endocannabinoid-like compounds was found in human neuroblastoma CHP100 and lymphoma U937 cells, and also in rat brain. Remarkably, human meningioma specimens showed an approximately six-fold smaller content of all N -acylethanolamines, but not of 2-AG, and a similar decrease was observed in a human glioblastoma. These ex vivo results fully support the purported roles of endocannabinoids in the nervous system. [source] Structure,Activity Relationships Among N -Arachidonylethanolamine (Anandamide) Head Group Analogues for the Anandamide TransporterJOURNAL OF NEUROCHEMISTRY, Issue 6 2000Abbas Jarrahian Abstract: Two putative endocannabinoids, N -arachidonylethanolamine (AEA) and 2-arachidonylglycerol, are inactivated by removal from the extracellular environment by a process that has the features of protein-mediated facilitated diffusion. We have synthesized and studied 22 N-linked analogues of arachidonylamide for the purpose of increasing our understanding of the structural requirements for the binding of ligands to the AEA transporter. We have also determined the affinities of these analogues for both the CB1 cannabinoid receptor and fatty acid amide hydrolase (FAAH). We have identified several structural features that enhance binding to the AEA transporter in cerebellar granule cells. We have confirmed the findings of others that replacing the ethanolamine head group with 4-hydroxybenzyl results in a high-affinity ligand for the transporter. However, we find that the same molecule is also a competitive inhibitor of FAAH. Similarly, replacement of the ethanolamine of AEA with 3-pyridinyl also results in a high-affinity inhibitor of both the transporter and FAAH. We conclude that the structural requirements for ligand binding to the CB1 receptor and binding to the transporter are very different; however, the transporter and FAAH share most, but not all, structural requirements. [source] Gastrointestinal Regulation of Food Intake: General Aspects and Focus on Anandamide and OleoylethanolamideJOURNAL OF NEUROENDOCRINOLOGY, Issue 2008R. Capasso The gastrointestinal tract plays a pivotal role in the regulation of food intake and energy balance. Signals from the gastrointestinal tract generally function to limit ingestion in the interest of efficient digestion. These signals may be released into the bloodstream or may activate afferent neurones that carry information to the brain and its cognitive centres, which regulates food intake. The rate at which nutrients become systemically available is also influenced by gastrointestinal motility: a delay in gastric emptying may evoke a satiety effect. Recent evidence suggests that the endocannabinoid anandamide and the related acylethanolamide oleoylethanolamide are produced in the intestine and might regulate feeding behaviour by engaging sensory afferent neurones that converge information to specific areas of the brain. The intestinal levels of these acylethanolamides are inversely correlated to feeding, as food deprivation increases intestinal levels of anandamide (which acts in the gut as a ,hunger signal'), while it decreases the levels of oleoylethanolamide (which acts in the gut as a ,satiety signal'). Additionally, these acylethanolamides, whose gastric levels change in response to diet-induced obesity, alter gastrointestinal motility, which might contribute to their effect on food intake and nutrient absorption. [source] Interplay Between Endocannabinoids, Steroids and Cytokines in the Control of Human ReproductionJOURNAL OF NEUROENDOCRINOLOGY, Issue 2008N. Battista The use of marijuana, which today is the most used recreational drug, has been demonstrated to affect adversely reproduction. Marijuana smokers, both men and women, show impaired fertility, owing to defective signalling pathways, aberrant hormonal regulation, or wrong timing during embryo implantation. Anandamide (N -arachidonoylethanolamine, AEA) and 2-arachidonoylglycerol (2-AG) mimic ,9 -tetrahydrocannabinol (THC), the psychoactive principle of Cannabis sativa, by binding to both the brain-type (CB1) and the spleen-type (CB2) cannabinoid receptors. These ,endocannabinoids' exert several actions either in the central nervous system or in peripheral tissues, and are metabolised by specific enzymes that synthesise or hydrolyse them. In this review, we shall describe the elements that constitute the endocannabinod system (ECS), in order to put in a better perspective the role of this system in the control of human fertility, both in females and males. In addition, we shall discuss the interplay between ECS, sex hormones and cytokines, which generates an endocannabinoid,hormone,cytokine array critically involved in the control of human reproduction. [source] Anandamide improves the impaired nitric oxide-mediated neurogenic relaxation of the corpus cavernosum in diabetic rats: involvement of cannabinoid CB1 and vanilloid VR1 receptorsBJU INTERNATIONAL, Issue 6 2007Mehdi Ghasemi OBJECTIVE To investigate the ability of acute administration of the endogenous cannabinoid, anandamide, in vitro to alter the nonadrenegic noncholinergic (NANC)-mediated relaxation of corpus cavernosum (CC) in diabetic rats and the possible role of nitric oxide (NO), as it is well known that erectile dysfunction (ED) affects 35,75% of men with diabetes mellitus and several studies have been conducted to find appropriate strategies for treating diabetes-induced ED. MATERIALS AND METHODS Diabetes was induced in rats by streptozotocin administration and was maintained for 8 weeks. The CC were removed and isolated in organ baths for pharmacological studies. Agonist-evoked or electrical-field stimulation (EFS)-evoked smooth muscle tensions in CC strips from control and diabetic rats were measured. RESULTS The neurogenic relaxation of phenylephrine (7.5 µm)-precontracted isolated CC strips was impaired in diabetic rats. Anandamide (0.3, 1 and 3 µm) enhanced the relaxant responses to EFS in diabetic CC strips in a dose-dependent manner. This effect was antagonized by the selective cannabinoid CB1 receptor antagonist AM251 (1 µm) and the selective vanilloid receptor antagonist capsazepine (3 µm). Concurrent administration of partially effective doses of l -arginine (10 µm) and anandamide (0.3 µm) exerted a synergistic improvement in EFS-induced relaxation of diabetic CC strips (P < 0.001). The relaxant responses to the NO donor, sodium nitroprusside, were similar between diabetic and control groups. CONCLUSION For the first time, we show that acute administration of anandamide, an endogenous cannabinoid, alone or combined with l -arginine can improve nitrergic nerve-mediated relaxation of the CC in diabetic rats. This effect was mediated by cannabinoid CB1 and vanilloid VR1 receptors within the CC. [source] Cannabinoids inhibit noradrenergic and purinergic sympathetic cotransmission in the rat isolated mesenteric arterial bedBRITISH JOURNAL OF PHARMACOLOGY, Issue 5 2007P Pakdeechote Background and purpose: Noradrenaline and ATP are sympathetic co-transmitters. In the rat perfused mesenteric bed cannabinoids have been shown to modify the overall response to sympathetic nerve stimulation. This study has assessed whether cannabinoid receptor activation modulates differentially the noradrenergic and purinergic components of sympathetic vasoconstriction. Experimental approach: Rat mesenteric beds were perfused with physiological salt solution and the effects of cannabinoids on responses to nerve stimulation, or exogenous noradrenaline or ,,, -methylene ATP (,,, -meATP; P2X receptor agonist) were determined after raising tone with U46619. The effects of cannabinoids on the noradrenaline and ATP components of sympathetic neurotransmission were assessed using the ,1 -adrenoceptor antagonist, prazosin, or after P2X receptor desensitization with ,,, -meATP. Key results: Anandamide, WIN 55,212-2 and CP55,940 attenuated sympathetic neurogenic vasoconstrictor responses. The inhibitory actions of anandamide and WIN 55,212-2 were blocked by LY320135, a CB1 receptor antagonist, but not by SR144528, a CB2 receptor antagonist. The inhibitory actions of CP55,940 were unaffected by LY320135 and SR144528. WIN 55,212-3, the inactive S(,) enantiomer of WIN 55,212-2, had no effect on sympathetic neurogenic responses. None of the cannabinoids affected contractile responses to exogenous noradrenaline or ,,, -meATP. Anandamide and WIN 55,212-2 inhibited both the noradrenaline and ATP components of the sympathetic neurogenic contractile responses, with effects on the ATP component being most marked. Conclusions and implications: These results indicate that prejunctional CB1 -like receptors mediate the sympathoinhibitory action of anandamide and WIN 55,212-2, but not CP55,940, in the rat mesenteric bed. Cannabinoids inhibit both the noradrenergic and purinergic components of sympathetic neurotransmission. British Journal of Pharmacology (2007) 152, 725,733; doi:10.1038/sj.bjp.0707397; published online 16 July 2007 [source] Anandamide mediates hyperdynamic circulation in cirrhotic rats via CB1 and VR1 receptorsBRITISH JOURNAL OF PHARMACOLOGY, Issue 7 2006L Moezi Background and purpose: Hyperdynamic circulation and mesenteric hyperaemia are found in cirrhosis. To delineate the role of endocannabinoids in these changes, we examined the cardiovascular effects of anandamide, AM251 (CB1 antagonist), AM630 (CB2 antagonist) and capsazepine (VR1 antagonist), in a rat model of cirrhosis. Experimental approach: Cirrhosis was induced by bile duct ligation. Controls underwent sham operation. Four weeks later, diameters of mesenteric arteriole and venule (intravital microscopy), arterial pressure, cardiac output, systemic vascular resistance and superior mesenteric artery (SMA) flow were measured after anandamide, AM251 (with or without anandamide), AM630 and capsazepine administration. CB1, CB2 and VR1 receptor expression in SMA was assessed by western blot and RT-PCR. Key results: Anandamide increased mesenteric vessel diameter and flow, and cardiac output in cirrhotic rats, but did not affect controls. Anandamide induced a triphasic arterial pressure response in controls, but this pattern differed markedly in cirrhotic rats. Pre-administration of AM251 blocked the effects of anandamide. AM251 (without anandamide) increased arterial pressure and systemic vascular resistance, constricted mesenteric arterioles, decreased SMA flow and changed cardiac output in a time-dependent fashion in cirrhotic rats. Capsazepine decreased cardiac output and mesenteric arteriolar diameter and flow, and increased systemic vascular resistance in cirrhotic rats, but lacked effect in controls. Expression of CB1 and VR1 receptor proteins were increased in cirrhotic rats. AM630 did not affect any cardiovascular parameter in either group. Conclusions and implications: These data suggest that endocannabinoids contribute to hyperdynamic circulation and mesenteric hyperaemia in cirrhosis, via CB1 - and VR1-mediated mechanisms. British Journal of Pharmacology (2006) 149, 898,908. doi:10.1038/sj.bjp.0706928 [source] Characterization of an anandamide degradation system in prostate epithelial PC-3 cells: synthesis of new transporter inhibitors as tools for this studyBRITISH JOURNAL OF PHARMACOLOGY, Issue 3 2004Lidia Ruiz-Llorente The response of anandamide is terminated by a carrier-mediated transport followed by degradation catalyzed by the cloned enzyme fatty acid amidohydrolase (FAAH). In this study, we provide biochemical data showing an anandamide uptake process and the expression of FAAH in human prostate. Anandamide was accumulated in PC-3 cells by a saturable and temperature-dependent process. Kinetic studies of anandamide uptake, determined in the presence of cannabinoid and vanilloid antagonists, revealed apparent parameters of KM=4.7±0.2 ,M and Vmax=3.3±0.3 pmol min,1 (106 cells),1. The accumulation of anandamide was moderately inhibited by previously characterized anandamide transporter inhibitors (AM404, UCM707 and VDM11) but was unaffected by inhibitors of other lipid transport systems (phloretin or verapamil) and moderately affected by the FAAH inhibitor methyl arachidonyl fluorophosphonate. The presence of FAAH in human prostate epithelial PC-3 cells was confirmed by analyzing its expression by Western blot and measuring FAAH activity. To further study the structural requirements of the putative carrier, we synthesized a series of structurally different compounds 1,8 and evaluated their capacity as uptake inhibitors. They showed different inhibitory capacity in PC-3 cells, with (9Z,12Z)- N -(fur-3-ylmethyl)octadeca-9,12-dienamide (4, UCM119) being the most efficacious, with maximal inhibition and IC50 values of 49% and 11.3±0.5 ,M, respectively. In conclusion, PC-3 cells possess a complete inactivation system for anandamide formed by an uptake process and the enzyme FAAH. These results suggest a possible physiological function of anandamide in the prostate, reinforcing the role of endocannabinoid system as a neuroendocrine modulator. British Journal of Pharmacology (2004) 141, 457,467. doi:10.1038/sj.bjp.0705628 [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] REVIEW FOR SPECIAL ISSUE ON CANNABINOIDS: Ligands that target cannabinoid receptors in the brain: from THC to anandamide and beyondADDICTION BIOLOGY, Issue 2 2008Roger G. Pertwee ABSTRACT A major finding,that (,)- trans -,9 -tetrahydrocannabinol (,9 -THC) is largely responsible for the psychotropic effects of cannabis,prompted research in the 1970s and 1980s that led to the discovery that this plant cannabinoid acts through at least two types of cannabinoid receptor, CB1 and CB2, and that ,9 -THC and other compounds that target either or both of these receptors as agonists or antagonists have important therapeutic applications. It also led to the discovery that mammalian tissues can themselves synthesize and release agonists for cannabinoid receptors, the first of these to be discovered being arachidonoylethanolamide (anandamide) and 2-arachidonoylglycerol. These ,endocannabinoids' are released onto their receptors in a manner that appears to maintain homeostasis within the central nervous system and sometimes either to oppose or to mediate or exacerbate the unwanted effects of certain disorders. This review provides an overview of the pharmacology of cannabinoid receptors and their ligands. It also describes actual and potential clinical uses both for cannabinoid receptor agonists and antagonists and for compounds that affect the activation of cannabinoid receptors less directly, for example by inhibiting the enzymatic hydrolysis of endocannabinoids following their release. [source] PRECLINICAL STUDY: Effect of cannabinoids on platelet serotonin uptakeADDICTION BIOLOGY, Issue 2 2007Marie Velenovská ABSTRACT Serotonin is involved in many of the same processes affected by cannabinoids; therefore, we investigated in vitro and in vivo effects of these drugs on the function of serotonin transporter. The effect of ,9 -tetrahydrocannabinol (,9 -THC), endocannabinoid anandamide and synthetic cannabinoid receptor agonist WIN 55,212-2 on platelet serotonin uptake and membrane microviscosity was examined in 19 marijuana smokers and 20 controls. (1) Serotonin uptake was inhibited at higher doses of ,9 -THC (IC50 = 139 µmol/l), anandamide (IC50 = 201 µmol/l) or WIN 55,212-2 (IC50 = 17.4 µmol/l); the inhibition was found non-competitive. ,9 -THC, anandamide and WIN 55,212-2 produced different effects on the membrane microviscosity. (2) Maximal velocity of platelet serotonin uptake was significantly increased in a group of chronic marijuana smokers suffering impairment of cognitive functions when compared with controls. Opposite effect of marijuana smoking on the serotonin uptake efficiency was observed in males beside females. In summary, this study provides evidence that (1) Activity of serotonin transporter is acutely affected by cannabinoids at relatively high drug concentrations; this effect is indirect and can be partially accounted for the changes in the membrane microviscosity. (2) Increase of maximal velocity of the serotonin uptake could be understood as adaptation change in the serotonergic system induced by chronic cannabis use. A hypothesis was supported that lowered serotonin uptake may reflect a gender-related differences in effects of psychoactive cannabinoids. [source] Study of the regulation of the endocannabinoid system in a virus model of multiple sclerosis reveals a therapeutic effect of palmitoylethanolamideEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2008Frida Loría Abstract Cannabinoids have recently been approved as a treatment for pain in multiple sclerosis (MS). Increasing evidence from animal studies suggests that this class of compounds could also prove efficient to fight neurodegeneration, demyelination, inflammation and autoimmune processes occurring in this pathology. However, the use of cannabinoids is limited by their psychoactive effects. In this context, potentiation of the endogenous cannabinoid signalling could represent a substitute to the use of exogenously administrated cannabinoid ligands. Here, we studied the expression of different elements of the endocannabinoid system in a chronic model of MS in mice. We first studied the expression of the two cannabinoid receptors, CB1 and CB2, as well as the putative intracellular cannabinoid receptor peroxisome proliferator-activated receptor-,. We observed an upregulation of CB2, correlated to the production of proinflammatory cytokines, at 60 days after the onset of the MS model. At this time, the levels of the endocannabinoid, 2-arachidonoylglycerol, and of the anti-inflammatory anandamide congener, palmithoylethanolamide, were enhanced, without changes in the levels of anandamide. These changes were not due to differences in the expression of the degradation enzymes, fatty acid amide hydrolase and monoacylglycerol lipase, or of biosynthetic enzymes, diacylglycerol lipase-, and N -acylphosphatidylethanolamine phospholipase-D at this time (60 days). Finally, the exogenous administration of palmitoylethanolamide resulted in a reduction of motor disability in the animals subjected to this model of MS, accompanied by an anti-inflammatory effect. This study overall highlights the potential therapeutic effects of endocannabinoids in MS. [source] Segregation of two endocannabinoid-hydrolyzing enzymes into pre- and postsynaptic compartments in the rat hippocampus, cerebellum and amygdalaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2004A. I. Gulyas Abstract Fatty acid amide hydrolase (FAAH) and monoglyceride lipase (MGL) catalyse the hydrolysis of the endocannabinoids anandamide and 2-arachidonoyl glycerol. We investigated their ultrastructural distribution in brain areas where the localization and effects of cannabinoid receptor activation are known. In the hippocampus, FAAH was present in somata and dendrites of principal cells, but not in interneurons. It was located mostly on the membrane surface of intracellular organelles known to store Ca2+ (e.g. mitochondria, smooth endoplasmic reticulum), less frequently on the somatic or dendritic plasma membrane. MGL immunoreactivity was found in axon terminals of granule cells, CA3 pyramidal cells and some interneurons. In the cerebellum, Purkinje cells and their dendrites are intensively immunoreactive for FAAH, together with a sparse axon plexus at the border of the Purkinje cell/granule cell layers. Immunostaining for MGL was complementary, the axons in the molecular layer were intensively labelled leaving the Purkinje cell dendrites blank. FAAH distribution in the amygdala was similar to that of the CB1 cannabinoid receptor: evident signal in neuronal somata and proximal dendrites in the basolateral nucleus, and hardly any labelling in the central nucleus. MGL staining was restricted to axons in the neuropil, with similar relative signal intensities seen for FAAH in different nuclei. Thus, FAAH is primarily a postsynaptic enzyme, whereas MGL is presynaptic. FAAH is associated with membranes of cytoplasmic organelles. The differential compartmentalization of the two enzymes suggests that anandamide and 2-AG signalling may subserve functional roles that are spatially segregated at least at the stage of metabolism. [source] Anandamide regulates neuropeptide release from capsaicin-sensitive primary sensory neurons by activating both the cannabinoid 1 receptor and the vanilloid receptor 1 in vitroEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2003Jatinder Ahluwalia Abstract The effect of anandamide, which activates both the cannabinoid 1 (CB1) receptor and the vanilloid receptor 1 (VR1), was studied on calcitonin gene-related peptide (CGRP) release from cultured primary sensory neurons, the majority of which coexpress the CB1 receptor and VR1. Concentrations of anandamide <,1 µm produced a small but significant CB1 receptor-mediated inhibition of basal CGRP release while higher concentrations induced VR1-mediated CGRP release. The excitatory effect of anandamide was potentiated by the CB1 receptor antagonist SR141716A. In the presence of SR141716A at concentrations <,100 nm, anandamide was equipotent with capsaicin in stimulating CGRP release. However, at higher concentrations anandamide produced more CGRP release than equimolar concentrations of capsaicin. Three and ten nanomolar anandamide inhibited the capsaicin-evoked CGRP release. In the presence of SR141716A, treatments which activated protein kinase A, protein kinase C and phospholipase C significantly potentiated the anandamide-evoked CGRP release at all anandamide concentrations. Although this potentiation was reduced when the CB1 receptor antagonist was omitted from the buffer, the CGRP release evoked by 300 nm and 1 µm anandamide was still significantly larger than that seen with nonpotentiated cells. These data indicate that anandamide may regulate CGRP release from capsaicin-sensitive primary sensory neurons in vivo, and that the net effect of anandamide on transmitter release from capsaicin-sensitive primary sensory neurons depends on the concentration of anandamide and the state of the CB1 receptor and VR1. These findings also suggest that anandamide could be one of the molecules responsible for the development of inflammatory heat hyperalgesia. [source] Intrathecally applied flurbiprofen produces an endocannabinoid-dependent antinociception in the rat formalin testEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2003Mehmet Ates Abstract It is generally accepted that the phospholipase-A2 -cyclooxygenase-prostanoids-cascade mediates spinal sensitization and hyperalgesia. However, some observations are not in line with this hypothesis. The aim of the present work was to investigate whether different components of this cascade exhibit nociceptive or antinociceptive effects in the rat formalin test. Intrathecal (i.th.) injection of prostaglandin E2 (PGE2) induced a dose-dependent antinociceptive effect on the formalin-induced nociception. Furthermore, thimerosal, which inhibits the reacylation of arachidonic acid thereby enhancing arachidonic acid levels, had an antinociceptive effect rather than the expected pronociceptive effect when given i.th. While the phospholipase A2 inhibitor methyl arachidonyl fluorophosphonate (MAFP; i.th.) had a significant antinociceptive effect, its analogue palmitoyl trifluoromethyl ketone (PTFMK; i.th.) had no significant effect on the formalin-induced nociception. However, MAFP, but not PTFMK, showed a cannabinoid CB1 agonistic effect as shown by the inhibition of electrically evoked contractions of the vas deferens isolated from CB1 wild-type mice but not of that from CB1 knockout mice. The antinociceptive effect of MAFP was completely reversed by the CB1 receptor antagonist AM-251 (i.th.), thus attributing such effect to its CB1 agonistic effect. Moreover, the antinociceptive effect of the cyclooxygenase inhibitor, flurbiprofen (i.th.) was reversed by the co-administration of AM-251, but not by PGE2. Finally. the combination of phenylmethylsulfonyl fluoride (PMSF; intraperitoneal), which inhibits the degradation of anandamide through the inhibition of fatty acid amidohydrolase, with thimerosal (i.th.) produced a profound CB1 -dependent antinociception. The present results show that endocannabinoids play a major role in mediating flurbiprofen-induced antinociception at the spinal level. [source] The uptake by cells of 2-arachidonoylglycerol, an endogenous agonist of cannabinoid receptorsFEBS JOURNAL, Issue 7 2001Tiziana Bisogno It is not yet clear if the endocannabinoid 2-arachidonoylglycerol (2-AG) is transported into cells through the same membrane transporter mediating the uptake of the other endogenous cannabinoid, anandamide (N -arachidonoylethanolamine, AEA), and whether this process (a) is regulated by cells and (b) limits 2-AG pharmacological actions. We have studied simultaneously the facilitated transport of [14C]AEA and [3H]2-AG into rat C6 glioma cells and found uptake mechanisms with different efficacies but similar affinities for the two compounds (Km 11.0 ± 2.0 and 15.3 ± 3.1 µm, Bmax 1.70 ± 0.30 and 0.24 ± 0.04 nmol·min,1·mg protein,1, respectively). Despite these similar Km values, 2-AG inhibits [14C]AEA uptake by cells at concentrations (Ki = 30.1 ± 3.9 µm) significantly higher than those required to either 2-AG or AEA to inhibit [3H]2-AG uptake (Ki = 18.9 ± 1.8 and 20.5 ± 3.2 µm, respectively). Furthermore: (a) if C6 cells are incubated simultaneously with identical concentrations of [14C]AEA and [3H]2-AG, only the uptake of the latter compound is significantly decreased as compared to that observed with [3H]2-AG alone; (b) the uptake of [14C]AEA and [3H]2-AG by cells is inhibited with the same potency by AM404 (Ki = 7.5 ± 0.7 and 10.2 ± 1.7 µm, respectively) and linvanil (Ki = 9.5 ± 0.7 and 6.4 ± 1.2 µm, respectively), two inhibitors of the AEA membrane transporter; (c) nitric oxide (NO) donors enhance the uptake of both [14C]AEA and [3H]2-AG, thus suggesting that 2-AG action can be regulated through NO release; (d) AEA and 2-AG induce a weak release of NO that can be blocked by a CB1 cannabinoid receptor antagonist, and significantly enhanced in the presence of AM404 and linvanil, thus suggesting that transport into C6 cells limits the action of both endocannabinoids. [source] Increased serum anandamide level at ruptured plaque site in patients with acute myocardial infarctionFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 3 2009Naotaka Maeda Abstract Inflammation caused by activated macrophages and T lymphocytes may trigger plaque rapture in acute coronary syndrome (ACS). Anandamide and 2-arachidonylglycerol (2-AG) are macrophage-derived signal lipids and may be involved in the pathogenesis of ACS, but no clinical relevant data have been reported. In 43 acute myocardial infarction (AMI) patients (66 ± 2 years), blood samples were obtained from the aortic root and the infarct-related coronary artery (IRA) using a PercuSurge system during primary percutaneous coronary intervention (PCI). In six patients with stable effort angina (SEA) (56 ± 6 years), blood samples were obtained from the site of stenosis during elective PCI. In 25 of the 43 AMI patients, anandamide was detected in the serum. Serum anandamide level was 35 ± 20 pmol/mL in the aorta and was significantly increased to 401 ± 134 pmol/mL in the IRA (P < 0.01). 2-AG was undetectable in most of the patients. In patients with SEA, neither anandamide nor 2-AG was detected in the serum at the plaque site. In AMI patients with anandamide detected, left ventricular ejection fraction at 2 weeks after PCI was increased by 3.7 ± 2.1% compared with that at the acute phase, while it was decreased by 3.0 ± 1.8% in those without anandamide detected (P < 0.05). The serum anandamide level at the culprit lesion was elevated compared with the systemic level in a significant number of AMI patients, indicating the synthesis of anandamide at the IRA. Anandamide was suggested to be derived from ruptured plaque and may exert beneficial effects in humans. [source] Augmentation of endogenous cannabinoid tone modulates lipopolysaccharide-induced alterations in circulating cytokine levels in ratsIMMUNOLOGY, Issue 2 2008Michelle Roche Summary The endogenous cannabinoid system plays an important role in regulating the immune system. Modulation of endogenous cannabinoids represents an attractive alternative for the treatment of inflammatory disorders. This study investigated the effects of URB597, a selective inhibitor of fatty acid amide hydrolase (FAAH), the enzyme catalysing degradation of the endogenous cannabinoid anandamide, and AM404, an inhibitor of anandamide transport, on lipopolysaccharide (LPS)-induced increases in plasma cytokine levels in rats. Both URB597 and AM404 potentiated the LPS-induced increase in plasma tumour necrosis factor-, (TNF-,) levels. The peroxisome proliferator-activated receptor , (PPAR,) antagonist, GW9662, attenuated the AM404-induced augmentation of TNF-, levels. Furthermore, the selective cannabinoid CB1 and CB2 receptor antagonists, AM251 and AM630 respectively, and the transient receptor potential vanilloid receptor-1 (TRPV1) antagonist, SB366791, reduced LPS-induced TNF-, plasma levels both alone and in combination with AM404. In contrast, AM404 inhibited LPS-induced increases in circulating interleukin-1, (IL-1,) and IL-6. AM251 attenuated the immunosuppressive effect of AM404 on IL-1,. None of the antagonists altered the effect of AM404 on LPS-induced IL-6. Moreover, AM251, AM630 and SB366791, administered alone, inhibited LPS-induced increases in plasma IL-1, and IL-6 levels. In conclusion, inhibition of endocannabinoid degradation or transport in vivo potentiates LPS-induced increases in circulating TNF-, levels, an effect which may be mediated by PPAR, and is also reduced by pharmacological blockade of CB1, CB2 and TRPV1. The immunosuppressive effect of AM404 on IL-1, levels is mediated by the cannabinoid CB1 receptor. Improved understanding of endocannabinoid-mediated regulation of immune function has fundamental physiological and potential therapeutic significance. [source] Synthesis of 15N-, 13C-, and 2H-labeled methanandamide analogsJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 2 2003Fen-Mei Yao Abstract Four isotopically labeled, metabolically stable analogs of arachidony-lethanolamide (anandamide), an endogenous cannabinoid ligand, were synthesized via a five-step reaction sequence starting from arachidonic acid. These stable methanandamide derivatives will serve as probes for studying the conformational properties of anandamide in model membrane systems using solid-state NMR spectroscopy. The synthetic methods described can be applied to the preparations of other anandamide analogs with isotopic labeling in different positions of the molecule, which could be utilized in biochemical and pharmacological experiments. Copyright © 2002 John Wiley & Sons, Ltd. [source] Mechanisms for recycling and biosynthesis of endogenous cannabinoids anandamide and 2-arachidonylglycerolJOURNAL OF NEUROCHEMISTRY, Issue 4 2008Ekaterina A. Placzek Abstract The mechanisms of endogenous cannabinoid biosynthesis are not completely understood. We hypothesized that anandamide could be recycled by the cell to form new endocannabinoid molecules and released into the extracellular space. We determined that new endocannabinoids derived from exogenous anandamide or arachidonic acid were synthesized and released from RBL-2H3 cells in response to ionomycin. Treatment of RBL-2H3 cells with nystatin and progesterone, agents that disrupt organization of lipid raft/caveolae, resulted in the attenuation of anandamide and 2-arachidonyl glycerol synthesis and/or release in response to stimulation with ionomycin suggesting a role for these membrane microdomains in endocannabinoid biosynthesis. Furthermore, anandamide synthesis may be independent of N -acyl phosphatidylethanolamine phospholipase D as expression of the enzyme was not detected in RBL-2H3 cells. We also established that extracellular calcium is necessary for endocannabinoid biosynthesis because release of intracellular calcium stores alone does not promote endocannabinoid biosynthesis. Next, we examined the role of calcium as a ,switch' to activate the synthesis of anandamide and simultaneously reduce uptake. Indeed, [3H] anandamide uptake was reduced in the presence of calcium. Our findings suggest a mechanism indicative of calcium-modulated activation of anandamide synthesis and simultaneous termination of uptake. [source] Anandamide administration alone and after inhibition of fatty acid amide hydrolase (FAAH) increases dopamine levels in the nucleus accumbens shell in ratsJOURNAL OF NEUROCHEMISTRY, Issue 2 2006Marcello Solinas Abstract Although endogenous cannabinoid systems have been implicated in the modulation of the rewarding effects of abused drugs and food, little is known about the direct effects of endogenous ligands for cannabinoid receptors on brain reward processes. Here we show for the first time that the intravenous administration of anandamide, an endogenous ligand for cannabinoid receptors, and its longer-lasting synthetic analog methanandamide, increase the extracellular dopamine levels in the nucleus accumbens shell of awake, freely moving rats, an effect characteristic of most drugs abused by humans. Anandamide produced two distinctly different effects on dopamine levels: (1) a rapid, transient increase that was blocked by the cannabinoid CB1 receptor antagonist rimonabant, but not by the vanilloid VR1 receptor antagonist capsazepine, and was magnified and prolonged by the fatty acid amide hydrolase (FAAH) enzyme inhibitor, URB597; (2) a smaller delayed and long-lasting increase, not sensitive to CB1, VR1 or FAAH blockade. Both effects were blocked by infusing either tetrodotoxin (TTX, 1 µm) or calcium-free Ringer's solution through the microdialysis probe, demonstrating that they were dependent on the physiologic activation of dopaminergic neurotransmission. Thus, these results indicate that anandamide, through the activation of the mesolimbic dopaminergic system, participates in the signaling of brain reward processes. [source] Cannabinoid,vanilloid receptor interactions in pain signalingJOURNAL OF NEUROCHEMISTRY, Issue 2003V. Di Marzo Agents that activate cannabinoid CB1 receptors for marijuana's active principal, THC, or vanilloid VR1 receptors for red chilli peppers' pungent ingredient, capsaicin, modulate pain perception. Stimulation of presynaptic CB1 leads to inhibition of glutamate release in the spinal cord, whereas VR1 stimulation causes release of substance P and CGRP from DRG neurons. VR1 undergoes rapid desensitization by its agonists, which makes VR1-expressing neurons insensitive to subsequent stimulation and results in analgesia. Thus, both CB1 and VR1, which are coexpressed in several spinal and DRG neurons, are targets for analgesic drug development. CB1 and VR1 also share endogenous agonists, namely anandamide, NADA and some of their analogs, and may be regarded as metabotropic and ionotropic receptors for the same family of mediators, with opposing roles in pain perception. The development of ,hybrid' CB1/VR1 agonists as potent analgesics and the functional relationships between CB1 and VR1 in sensory neurons will be discussed. [source] Characterization of VR1 within the BMBF-Leitproject: ,Molecular Pain Research'JOURNAL OF NEUROCHEMISTRY, Issue 2003R. Jostock The vanilloid receptor VR1 is a ligand, heat and proton gated ion channel, expressed predominantly by primary sensory neurons. We show the molecular characterization of VR1 and its involvement in nociceptive behavior. Biochemical analysis of VR1 showed glycosylation at N604 and the predicted tetrameric structure. Reduced pH potentiated the gating of the receptor by NADA and anandamide in recombinant VR1. Acidification could sensitize VR1 and lead to hyperalgesia. Therefore, the VR1 antagonist capsazepine was tested in several animal models. Capsazepine reduced formalin induced nocifensive behavior and CFA induced mechanical hyperalgesia, and was antiallodynic and antihyperalgesic in animal models of neuropathic pain. VR1 antisense oligonucleotides inhibited VR1 expression in vitro and reduced tactile allodynia in vivo. In conclusion, we could provide evidence for a role of VR1 in inflammatory and neuropathic pain pathways. [source] Levodopa treatment reverses endocannabinoid system abnormalities in experimental parkinsonismJOURNAL OF NEUROCHEMISTRY, Issue 4 2003Mauro Maccarrone Abstract Cannabinoid receptors and their endogenous ligands are potent inhibitors of neurotransmitter release in the brain. Here, we show that in a rat model of Parkinson's disease induced by unilateral nigral lesion with 6-hydroxydopamine (6-OHDA), the striatal levels of the endocannabinoid anandamide (AEA) were increased, while the activity of its membrane transporter and hydrolase (fatty-acid amide hydrolase, FAAH) were decreased. These changes were not observed in the cerebellum of the same animals. Moreover, the frequency and amplitude of glutamate-mediated spontaneous excitatory post-synaptic currents were augmented in striatal spiny neurones recorded from parkinsonian rats. Remarkably, the anomalies in the endocannabinoid system, as well as those in glutamatergic activity, were completely reversed by chronic treatment of parkinsonian rats with levodopa, and the pharmacological inhibition of FAAH restored a normal glutamatergic activity in 6-OHDA-lesioned animals. Thus, the increased striatal levels of AEA may reflect a compensatory mechanism trying to counteract the abnormal corticostriatal glutamatergic drive in parkinsonian rats. However, this mechanism seems to be unsuccessful, since spontaneous excitatory activity is still higher in these animals. Taken together, these data show that anomalies in the endocannabinoid system induced by experimental parkinsonism are restricted to the striatum and can be reversed by chronic levodopa treatment, and suggest that inhibition of FAAH might represent a possible target to decrease the abnormal cortical glutamatergic drive in Parkinson's disease. [source] Gas chromatography,mass spectrometry analysis of endogenous cannabinoids in healthy and tumoral human brain and human cells in cultureJOURNAL OF NEUROCHEMISTRY, Issue 2 2001Mauro Maccarrone Endocannabinoids are lipid mediators thought to modulate central and peripheral neural functions. We report here gas chromatography,electron impact mass spectrometry analysis of human brain, showing that lipid extracts contain anandamide and 2-arachidonoylglycerol (2-AG), the most active endocannabinoids known to date. Human brain also contained the endocannabinoid-like compounds N -oleoylethanolamine, N -palmitoylethanolamine and N -stearoylethanolamine. Anandamide and 2-AG (0.16 ± 0.05 and 0.10 ± 0.05 nmol/mg protein, respectively) represented 7.7% and 4.8% of total endocannabinoid-like compounds, respectively. N -Palmitoyethanolamine was the most abundant (50%), followed by N -oleoyl (23.6%) and N -stearoyl (13.9%) ethanolamines. A similar composition in endocannabinoid-like compounds was found in human neuroblastoma CHP100 and lymphoma U937 cells, and also in rat brain. Remarkably, human meningioma specimens showed an approximately six-fold smaller content of all N -acylethanolamines, but not of 2-AG, and a similar decrease was observed in a human glioblastoma. These ex vivo results fully support the purported roles of endocannabinoids in the nervous system. [source] Gastrointestinal Regulation of Food Intake: General Aspects and Focus on Anandamide and OleoylethanolamideJOURNAL OF NEUROENDOCRINOLOGY, Issue 2008R. Capasso The gastrointestinal tract plays a pivotal role in the regulation of food intake and energy balance. Signals from the gastrointestinal tract generally function to limit ingestion in the interest of efficient digestion. These signals may be released into the bloodstream or may activate afferent neurones that carry information to the brain and its cognitive centres, which regulates food intake. The rate at which nutrients become systemically available is also influenced by gastrointestinal motility: a delay in gastric emptying may evoke a satiety effect. Recent evidence suggests that the endocannabinoid anandamide and the related acylethanolamide oleoylethanolamide are produced in the intestine and might regulate feeding behaviour by engaging sensory afferent neurones that converge information to specific areas of the brain. The intestinal levels of these acylethanolamides are inversely correlated to feeding, as food deprivation increases intestinal levels of anandamide (which acts in the gut as a ,hunger signal'), while it decreases the levels of oleoylethanolamide (which acts in the gut as a ,satiety signal'). Additionally, these acylethanolamides, whose gastric levels change in response to diet-induced obesity, alter gastrointestinal motility, which might contribute to their effect on food intake and nutrient absorption. [source] |