“CB1 receptor antagonists have been shown to prevent acute and long-term behavioral effects of cocaine. Here we evaluate the effectiveness of the CB1 receptor antagonist rimonabant to modify sensitized responses to cocaine. Our findings add to the evidence that drugs targeting CB1 receptors are good candidates for the treatment of cocaine abuse and provide further insights into the mechanisms underlying endocannabinoid signaling within the brain reward system in the context of cocaine abuse.” https://www.ncbi.nlm.nih.gov/pubmed/28366798]]>
Category Archives: Endocannabinoid System
[Role of cannabinoid receptor 1-mediated synaptic plasticity in neuropathic pain and associated depression].
“Neuropathic pain is a class of pain caused by an injury or diseases of the somatosensory system and characterized by spontaneous pain, allodynia, and hyperalgesia. It is well established that central sensitization is one of the key mechanisms underlying the development and maintenance of neuropathic pain. Cannabinoid receptor 1 (CB1R) of endocannabinoid system modulates synaptic transmission, regulates synaptic plasticity, inhibits central sensitization, and thus attenuates neuropathic pain. Recent studies have shown that activation of CB1R also involves in the relief of neuropathic pain-induced depression.” https://www.ncbi.nlm.nih.gov/pubmed/28364110
The effect of cannabinoid receptor 1 blockade on hepatic free fatty acid profile in mice with nonalcoholic fatty liver disease.
“We used rimonabant to investigate the role of CB1 receptor on hepatic FFAs profile during NAFLD. Male mice C57BL/6 were divided into: control group fed with control diet 20 weeks (C; n=6); group fed with HFD 20 weeks (HF; n=6); group fed with control diet and treated with rimonabant after 18 weeks (R; n=9); group fed with HFD and treated with rimonabant after 18 weeks (HFR; n=10). Rimonabant (10mg/kg) was administered daily to HFR and R group by oral gavage. Rimonabant decreased liver palmitic acid proportion in HFR group compared to HF group (p<0.05). Liver stearic and oleic acid proportions were decreased in R group compared to control (p<0.01 respectively). Rimonabant increased liver linoleic and arachidonic acid proportions in HFR group compared to HF group (p<0.01 respectively). CB1 blockade may be useful in the treatment of HFD-induced NAFLD due to modulation of plasma lipid and hepatic FFA profile.” https://www.ncbi.nlm.nih.gov/pubmed/28363784 http://www.sciencedirect.com/science/article/pii/S0009308417300063]]>
Genetic or pharmacological depletion of cannabinoid CB1 receptor protects against dopaminergic neurotoxicity induced by methamphetamine in mice.
“Accumulating evidence suggests that cannabinoid ligands play delicate roles in cell survival and apoptosis decisions, and that cannabinoid CB1 receptors (CB1R) modulate dopaminergic function. However, the role of CB1R in methamphetamine (MA)-induced dopaminergic neurotoxicity in vivo remains elusive. Multiple high doses of MA increased phospho-ERK and CB1R mRNA expressions in the striatum of CB1R (+/+) mice. These increases were attenuated by CB1R antagonists (i.e., AM251 and rimonabant), an ERK inhibitor (U0126), or dopamine D2R antagonist (sulpiride). CB1R agonist-induced toxic effects were significantly attenuated by CB1R knockout, CB1R antagonists or PKCδ knockout. Therefore, our results suggest that interaction between D2R, ERK and CB1R is critical for MA-induced dopaminergic neurotoxicity and that PKCδ mediates dopaminergic damage induced by high-doses of CB1R agonist.” https://www.ncbi.nlm.nih.gov/pubmed/28363605]]>
Comparative antinociceptive effect of arachidonylcyclopropylamide, a cannabinoid 1 receptor agonist & lignocaine, a local anaesthetic agent, following direct intrawound administration in rats.
“Treatment of inflammatory pain with opioids is accompanied by unpleasant and, at times, life-threatening side effects.
Cannabis produces antinociception as well as psychotropic effects. It was hypothesized that peripheral cannabinoid receptors outside the central nervous system could be selectively activated for relief of pain.
This study was undertaken to measure the antinociceptive effect of type 1 cannabinoid receptor (CB1r) agonist arachidonylcyclopropylamide (ACPA) in a rat model of inflammatory pain after intrawound administration and the effects were compared with lignocaine.
Lignocaine attenuated evoked pain behaviour whereas ACPA decreased guarding score. This difference was likely due to blockade of sodium ion channels and the activation of peripheral CB1r, respectively. Central side effects were absent after ACPA treatment. Further studies need to be done to assess the effect of ACPA treatment in clinical conditions.”
https://www.ncbi.nlm.nih.gov/pubmed/28361827