Cannabinoid receptor antagonists counteract sensorimotor gating deficits in the phencyclidine model of psychosis.
Martina Ballmaier, Marco Bortolato, Cristina Rizzetti, Michele Zoli, GianLuigi Gessa, Andreas Heinz, PierFranco Spano
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology October 1, 2007 DOI: 10.1038/sj.npp.1301344 via PubMed
Summary
AI-generated from the abstractCB1 receptor antagonists rimonabant and AM251 reversed deficits in sensorimotor gating caused by phencyclidine in rats, an effect comparable to the atypical antipsychotic clozapine. Rimonabant also attenuated gating disruptions from dizocilpine and apomorphine. No augmentation was seen when rimonabant and clozapine were given together. The findings suggest that blocking CB1 receptors may help restore disrupted interactions between the endocannabinoid and glutamate systems implicated in schizophrenia.
Study at a glance
| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | Rats |
| Interventions | rimonabant AM251 clozapine |
| Key finding | CB1 receptor antagonists rimonabant and AM251 reversed phencyclidine-induced deficits in prepulse inhibition in rats, mimicking the atypical antipsychotic profile of clozapine. |
Abstract
Clinical and laboratory findings suggest that cannabinoids and their receptors are implicated in schizophrenia. The role of cannabinoids in schizophrenia remains however poorly understood, as data are often contradictory. The primary aim of this study was to investigate whether the cannabinoid CB1 receptor antagonists rimonabant and AM251 are able to reverse deficits of sensorimotor gating induced by phencyclidine and to mimic the 'atypical' antipsychotic profile of clozapine. The prepulse inhibition (PPI) of the startle reflex was used to measure deficits of sensorimotor gating. PPI-disruptive effects of phencyclidine and their antagonism by rimonabant, AM251, and clozapine were studied in rats. The effects of rimonabant were carefully examined taking into account dose ranges, vehicle, and route of administration. We also examined the ability of rimonabant to reduce the PPI-disruptive effects of dizocilpine and apomorphine. Rimonabant as well as AM251 significantly counteracted the phencyclidine-disruptive model of PPI, comparable to the restoring effect of clozapine; no augmentation effect was observed with rimonabant and clozapine as cotreatment. Rimonabant also significantly attenuated the PPI disruptive effects of dizocilpine and apomorphine. Taken together, our results indicate that CB1 receptor antagonists do produce 'atypical' antipsychotic profile mimicking that of clozapine in the phencyclidine disruption of sensorimotor gating. Our findings further suggest that CB1 receptor antagonism may be involved in restoring disturbed interactions between the activity of the endocannabinoid system and glutamate neurotransmitter system implied in schizophrenia.