Effects of chronic nicotine on food intake and anxiety-like behaviour in CB(1) knockout mice.

We have evaluated the effects of chronic nicotine administration and withdrawal in food intake and preference, metabolic parameters and anxiety-like behaviour in CB(1) knockout mice and wild-type littermates. Mutant mice showed lower levels of glucose, insulin and cholesterol after two weeks of high fat diet and reduced preference for saccharin solution when compared with wild-type mice. Nicotine reduced body weight and induced anxiogenic-like effects in wild-type, but not in CB(1) knockout mice. Our results suggest a modulatory role of the endocannabinoid system on the effects induced by nicotine on metabolic parameters and anxiety-like responses.