Despite the fact that the cannabinoid receptor type 1 (CB1R) plays a pivotal role in emotional memory processing in different regions of the brain, its function in the retrosplenial cortex (RSC) remains unknown. Here, using contextual fear conditioning in rats, we showed that a post-training intra-RSC infusion of the CB1R antagonist AM251 impaired, and the agonist CP55940 improved, long-term me...

The receptors mediating the hemodynamic responses to cannabinoids are not clearly defined due to the multifarious pharmacology of many commonly used cannabinoid ligands. While both CB1 and TRPV1 receptors are implicated, G protein-coupled receptor 55 (GPR55) may also mediate some of the hemodynamic effects of several atypical cannabinoid ligands. The present studies attempted to unravel the pha...

The endocannabinoid (eCB) system is an important regulator of the stress response and mediates several stress-related behaviors, including anxiety. Despite anatomical evidence that eCBs interact with the principle stress peptide, corticotropin-releasing factor (CRF), few data exist that address functional interactions between these systems. Accordingly, we examined the effects of the CB1 recept...

Clinical and laboratory studies suggest that the endocannabinoid system is involved in schizophrenia disorders. Recent evidence indicates that cannabinoid receptor (CB1) antagonists have a pharmacological profile similar to antipsychotic drugs. We investigated the behavioural and biochemical effects of the CB1 antagonist AM251 in a phencyclidine (PCP) animal paradigm modelling the cognitive def...

Chen, R. Z., R. R. Huang, et al. (2004). "Synergistic effects of cannabinoid inverse agonist AM251 and opioid antagonist nalmefene on food intake in mice." Brain Res 999(2): 227-30. Oral administration of the opioid antagonist nalmefene alone (up to 20 mg/kg) failed to show a significant effect on acute food intake in mice. However, combined oral dosing of nalmefene and subthreshold doses of AM...

In contrast to the adult brain, the adult spinal cord is a non-neurogenic environment. Understanding how to manipulate the spinal cord environment to promote the formation of new neurons is an attractive therapeutic strategy for spinal cord injury and disease. The cannabinoid 1 receptor (CB1R) has been implicated as a modulator of neural progenitor cell proliferation and fate specification in t...

AIM The aim of the present study was to determine whether the endocannabinoid system could be involved in the ethanol-induced inhibition of salivation in adult male Wistar rats. METHODS Salivary secretion induced by different concentrations of methacholine, a cholinergic agonist, and the endocannabinoid arachidonoyl ethanolamide (anandamide, AEA) production in the submandibular gland (SMG) we...

Cannabinoid receptors 1 (CB1R) have been shown to be a crucial part of the neuromodulatory endocannabinoid system which is involved in emotional learning and memory. We here investigated in rats the role of CB1R in the basolateral amygdala (BLA) and medial prefrontal cortex (mPFC) in different phases of fear learning, memory and extinction. We used the fear potentiated startle paradigm to measu...

Type 1 cannabinoid (CB1) receptors mediate widespread synaptic plasticity, but how this contributes to systems-level plasticity and development in vivo is unclear. We tested whether CB1 signaling is required for development and plasticity of the whisker map in rat somatosensory cortex. Treatment with the CB1 antagonist AM251 during an early critical period for layer (L) 2/3 development (beginni...

Recent studies have shown that the activated endocannabinoid system participates in the increase in IHR (intrahepatic resistance) in cirrhosis. The increased hepatic production of vasoconstrictive eicosanoids is involved in the effect of endocannabinoids on the hepatic microcirculation in cirrhosis; however, the mechanisms of these effects are still unknown. The aim of the present study was to ...