Stimulation of accumbens shell cannabinoid CB 1 receptors by noladin ether, a putative endocannabinoid, modulates food intake and dietary selection in rats

摘要

Stimulation of cannabinoid CB 1 receptors in nucleus accumbens shell has been shown to stimulate feeding and enhance positive 'liking' reactions to intraoral sucrose. This study examined the behavioural effects of noladin ether and 2-arachidonoylglycerol following infusion into accumbens shell, on chow intake and food preference in high-carbohydrate and high-fat preferring rats. Noladin ether, potently and dose-dependently stimulated chow intake as compared with 2-arachidonoylglycerol in free-feeding rats. In the diet preference paradigm, in which rats were given free access to both, high-carbohydrate (HC) and high-fat (HF) diets simultaneously, an intra-accumbens administration of noladin ether as well as 2- arachidonoylglycerol, preferentially enhanced fat consumption over carbohydrate in both HF- and HC-preferring rats. These effects were significantly attenuated by the CB 1 receptor antagonist, AM 251. These results suggesting that, the endocannabinoids through CB 1 receptors, affects appetite for specific dietary components. Both these agents exert a specific action on eating motivation and possibly promoting eating by enhancing the incentive value of food. Altogether these findings reinforce the idea that the endogenous cannabinoid system in the accumbens shell may be important to augment reward-driven feeding via modulation of CB 1 receptor signalling pathways.