Delta-9-tetrahydrocannabinol interferes with the establishment and the expression of conditioned rejection reactions produced by cyclophosphamide

Abstract
RELIABLE animal models of nausea are necessary to better understand the neurobiology of nausea and to assess treatment effectiveness. We present such a model based on conditioned rejection reactions in rats. Our results demonstrate that delta-9-tetrahydrocannabinol (THC), a treatment reported to reduce chemotherapy-induced nausea in humans, also reduces conditioned rejection reactions in rats. Rats were administered THC or vehicle prior to a pairing of saccharin solution with cyclophosphamide or saline during conditioning and/or prior to test. THC interfered with the establishment of cyclophsophamide-induced conditioned rejection during conditioning and with the expression of conditioned rejection during testing. Our results confirm that the conditioned rejection reaction in the rat is a useful animal model of nausea.