Cannabinoid ligands show therapeutic potential in a variety of disorders including anxiety. However, the anxiety-related effects of cannabinoids remain controversial as agonists show opposite effects in mice and rats. Here we compared the effects of the cannabinoid agonist WIN-55,212 and the CB1 antagonist AM-251 in CD1 mice and Wistar rats. Special attention was paid to antagonist-agonist inte...

Oleamide (cis-9-octadecenoamide) exhibits some cannabimimetic responses despite its low affinities at the currently known cannabinoid receptors. Here we have investigated whether or not it is a vasorelaxant in rat small mesenteric arteries. Oleamide elicited vasorelaxation (EC50=1.2+/-0.2 microM, Rmax=99.1+/-3.9%, n=8) which was reduced by endothelial removal. Nitric oxide synthase inhibition r...

Based on numerous pharmacological studies that have revealed an interaction between cannabinoid and opioid systems at the molecular, neurochemical, and behavioral levels, a new series of hybrid molecules has been prepared by coupling the molecular features of two wellknown drugs, ie, rimonabant and fentanyl. The new compounds have been tested for their affinity and functionality regarding CB1 a...

Previous evidence suggests that the endogenous cannabinoid system could emerge and be operative early during brain development. In the present study, we have explored the distribution of specific binding for cannabinoid receptors in rat brain at gestational day 21 (GD21), postnatal days 5 (PND5) and 30 (PND30), and at adult age (> 70 days after birth) by using autoradiography with [3H]CP-55,940...

The CB1 cannabinoid receptor antagonist SR 141716A abolished the inhibition of Ca2+ currents by the agonist WIN 55,212-2. However, SR 141716A alone increased Ca2+ currents, with an EC50 of 32 nM, in neurons that had been microinjected with CB1 cRNA. For an antagonist to elicit an effect, some receptors must be tonically active. Evidence for tonically active CB1 receptors was seen as enhanced to...

Synthesis of an antagonist, SR141716A, that selectively binds to brain cannabinoid (CB(1)) receptors without producing cannabimimetic activity in vivo, suggests that recognition and activation of cannabinoid receptors are separable events. In the present study, a series of SR141716A analogs were synthesized and were tested for CB(1) binding affinity and in a battery of in vivo tests, including ...

AIMS The cannabinoid CB1 receptor antagonist, SR141716A, differentially affects the ethanol preference of chronically alcoholized rats when administered during cycles of ethanol exposure and withdrawal. In this study, ethanol preference was investigated in chronically alcoholized rats that underwent regular withdrawal periods during which the brain cannabinoid CB(1) receptor antagonist, SR14171...

BACKGROUND Cannabinoids, the active components of marijuana, stimulate appetite, and cannabinoid receptor-1 (CB1-R) antagonists suppress appetite and promote weight loss. Little is known about how CB1-R antagonists affect the central neurocircuitry, specifically the melanocortin system that regulates energy balance. METHODOLOGY/PRINCIPAL FINDINGS Here, we show that peripherally administered C...

Introduction: Previous studies have shown that cannabinoidergic system is involved in anxiety. However, there are controversial reports in the experimental studies. The aim of this study is to evaluate the effect of pharmacological stimulation or blocking of CB1 receptors and inhibition of endocannabinoid degradation in anxiety like behavior in elevated plus-maze (EPM) test in rat. The EPM is o...

Previous experimental studies have shown that various anesthetics alter the effects of cannabinoid agonists and antagonists on the cardiac response to different stimuli. Since no data have shown an interaction between urethane and cannabinoid signaling in epilepsy, we examined the suitability of urethane with regard to testing the effects of a cannabinoid CB1 receptor agonist and an antagonist ...