Search results for "CB1"
showing 10 items of 146 documents
The atypical cannabinoid O-1602 protects against experimental colitis and inhibits neutrophil recruitment.
2011
Background: Cannabinoids are known to reduce intestinal inflammation. Atypical cannabinoids produce pharmacological effects via unidentified targets. We were interested in whether the atypical cannabinoid O-1602, reportedly an agonist of the putative cannabinoid receptor GPR55, reduces disease severity of dextran sulfate sodium (DSS) and trinitrobenzene sulfonic acid (TNBS)-induced colitis in C57BL/6N and CD1 mice. Methods: DSS (2.5% and 4%) was supplied in drinking water for 1 week while TNBS (4 mg) was applied as a single intrarectal bolus. Results: Both treatments caused severe colitis. Injection of O-1602 (5 mg/kg intraperitoneally) significantly reduced macroscopic and histological col…
Biphasic effects of cannabinoids in anxiety responses: CB1 and GABA(B) receptors in the balance of GABAergic and glutamatergic neurotransmission
2012
Biphasic effects of cannabinoids have been shown in processes such as feeding behavior, motor activity, motivational processes and anxiety responses. Using two different tests for the characterization of anxiety-related behavior (elevated plus-maze and holeboard), we first identified in wild-type C57BL/6N mice, two doses of the synthetic CB1 cannabinoid receptor agonist CP-55,940 with anxiolytic (1 mug/kg) and anxiogenic properties (50 mug/kg), respectively. To clarify the role of CB1 receptors in this biphasic effect, both doses were applied to two different conditional CB1 receptor knockout (KO) mouse lines, GABA-CB1-KO (CB1 receptor inactivation in forebrain GABAergic neurons) and Glu-CB…
CB1 cannabinoid receptor-mediated aggressive behavior
2013
This study examined the role of cannabinoid CB1 receptors (CB1r) in aggressive behavior. Social encounters took place in grouped and isolated mice lacking CB1r (CB1KO) and in wild-type (WT) littermates. Cognitive impulsivity was evaluated in the delayed reinforcement task (DRT). Gene expression analyses of monoaminooxidase-A (MAO-A), catechol-o-methyl-transferase (COMT), 5-hydroxytriptamine transporter (5-HTT) and 5-HT1B serotonergic receptor (5HT1Br) in the median and dorsal raphe nuclei (MnR and DR, respectively) and in the amygdala (AMY) were performed by real time-PCR. Double immunohistochemistry studies evaluated COMT and CB1r co-localization in the raphe nuclei and in the cortical (AC…
Interaction between cannabinoid CB1 receptors and endogenous ATP in the control of spontaneous mechanical activity in mouse ileum
2009
Background and purpose Although it is well accepted that cannabinoids modulate intestinal motility by reducing cholinergic neurotransmission mediated by CB(1) receptors, it is not known whether the endocannabinoids are involved in more complex circuits and if they interact with other systems. The aim of the present study was to examine possible interactions between cannabinoid CB(1) receptors and purines in the control of spontaneous contractility of longitudinal muscle in mouse ileum. Experimental approach The mechanical activity of longitudinally oriented ileal segments from mice was recorded as isometric contractions. Key results The selective CB(1) receptor agonist, N-(2-chloroethyl)5,8…
Pharmacological blockade of the fatty acid amide hydrolase (FAAH) alters neural proliferation, apoptosis and gliosis in the rat hippocampus, hypothal…
2015
Endocannabinoids participate in the control of neurogenesis, neural cell death and gliosis. The pharmacological effect of the fatty acid amide hydrolase (FAAH) inhibitor URB597, which limits the endocannabinoid degradation, was investigated in the present study. Cell proliferation (phospho-H3(+) or BrdU(+) cells) of the main adult neurogenic zones as well as apoptosis (cleaved caspase-3(+)), astroglia (GFAP(+)), and microglia (Iba1(+) cells) were analyzed in the hippocampus, hypothalamus and striatum of rats intraperitoneally treated with URB597 (0.3 mg/kg/day) at one dose/4-days resting or 5 doses (1 dose/day). Repeated URB597 treatment increased the plasma levels of the N-acylethanolamine…
Cannabinoid CB1 receptor activation modulates spontaneous contractile activity in mouse ileal longitudinal muscle.
2007
The purpose of the present study was to examine whether cannabinoid receptor agonists influence spontaneous contractile activity of longitudinal muscle in mouse ileum in vitro. Isolated segments of mouse ileum displayed spontaneous contractions with an amplitude and frequency of about 300 mg and 30 cpm, respectively. The endocannabinoid anandamide (1-100 microM), the selective cannabinoid CB(1) receptor agonist, ACEA (0.1 microM-10 microM), but not the selective cannabinoid CB(2) receptor agonist, JWH 133 (0.1 microM-10 microM), reduced in a concentration-dependent manner the spontaneous mechanical activity. The inhibitory effect consisted in a decrease of the mean amplitude of longitudinal…
Cannabis and the Mesolimbic System
2016
Abstract Cannabis sativa (hemp) is a flowering annual plant whose phytochemical by-products, hashish and marihuana, are the most widely produced and most frequently used illicit drugs in Europe. Δ 9 -Tetrahydrocannabinol is the primary psychoactive constituent, responsible, in a dose-related manner, for euphoria, cognitive effects, and psychotic symptoms, as well as the addictive potential of smoked cannabis due to its interference with the mesolimbic dopaminergic system. Cannabis as well as endocannabinoids acts mainly at the presynaptic levels in several brain regions, including the nucleus accumbens and ventral tegmental area, where it modulates synaptic activity. Through the modulation …
Plasma membrane and lysosomal localization of CB1 cannabinoid receptor are dependent on lipid rafts and regulated by anandamide in human breast cance…
2005
AbstractIn this report we show, by confocal analysis of indirect immunofluorescence, that the type-1 cannabinoid receptor (CB1R), which belongs to the family of G-protein-coupled receptors, is expressed on the plasma membrane in human breast cancer MDA-MB-231 cells. However, a substantial proportion of the receptor is present in lysosomes. We found that CB1R is associated with cholesterol- and sphyngolipid-enriched membrane domains (rafts). Cholesterol depletion by methyl-β-cyclodextrin (MCD) treatment strongly reduces the flotation of the protein on the raft-fractions (DRM) of sucrose density gradients suggesting that CB1 raft-association is cholesterol dependent. Interestingly binding of …
Cannabinoid type-1 receptor signaling in central serotonergic neurons regulates anxiety-like behavior and sociability.
2015
The endocannabinoid (eCB) system possesses neuromodulatory functions by influencing the release of various neurotransmitters, including γ-aminobutyric acid (GABA) and glutamate. A functional interaction between eCBs and the serotonergic system has already been suggested. Previously, we showed that cannabinoid type-1 (CB1) receptor mRNA and protein are localized in serotonergic neurons of the raphe nuclei, implying that the eCB system can modulate serotonergic functions. In order to substantiate the physiological role of the CB1 receptor in serotonergic neurons of the raphe nuclei, we generated serotonergic 5-hydroxytryptamine (5-HT) neuron-specific CB 1 receptor-deficient mice, using the Cr…
Evidence for a modulatory role of cannabinoids on the excitatory NANC neurotransmission in mouse colon
2007
Abstract It is well accepted that endogenous cannabinoids and CB1 receptors are involved in the regulation of smooth muscle contractility and intestinal motility, through a mechanism mainly related to reduction of acetylcholine release from cholinergic nerve endings. Because, few data exist on a possible modulatory action of the cannabinoid agents on the non-adrenergic non-cholinergic (NANC) excitatory and inhibitory neurotransmission, the aim of the present study was to investigate the effects of cannabinoid drugs on the NANC responses elicited by electrical field stimulation (EFS) in the circular muscle of mouse proximal colon. Colonic contractions were monitored as changes in endoluminal…