EFFECTS OF RIMONABANT ON ACTIVE AVOIDANCE LEARNING IN BULBECTOMIZED RATS

Abstract

The abnormal activity of endocannabinoid system has been implicated in the mechanisms of some psychiatric and neurological disorders. Olfactory bulbectomy (OBX) is an animal model of depression. We examined the effect of the CB1 antagonist Rimonabant (RIM) on the learning and memory processes of OBX rats tested in an active avoidance paradigm. RIM was administeredbyintragastric cannula to OBX rats once daily for 14 days. OBX rats were divided into three groups, and RIM was given before; immediately after; or 14 days after OBX. RIM showed a memory enhancing effect in the sham-operated rats and partially ameliorated the memory disturbances induced by the bulbectomy, given before OBX or 14 days after OBX. Only upon administration immediately after OBX, it prevented the development of the memory deficits. The study provides evidence that impaired endocannabinoid signalling may be involved in the development of cognitive deficits accompanying the OBX syndrome.

Keywords

• olfactory bulbectomy
• cannabinoid receptor
• memory
• rat