NITRIC-OXIDE SYNTHASE INHIBITION AND FOOD-INTAKE - EFFECTS ON MOTIVATION TO EAT AND IN FEMALE MICE

Recent studies have demonstrated that nitric oxide may play an importa nt role in the regulation of food intake. The studies reported here ex tend these findings by demonstrating that N-G-nitro-arginine-methylest er, N-Arg(ME), a nitric oxide synthase inhibitor, decreased intake of a highly palatable substance (i.e., milk), though at a higher dose tha n necessary for decreasing consumption of food pellets. N-Arg(ME) fail ed to inhibit lever press for milk reward in nonprefed mice, but decre ased lever pressing in prefed mice. N-Arg(ME) decreased food intake in female mice, being most potent in proestrus. These studies suggest th at nitric oxide synthase inhibition decreases food intake without indu cing aversion or illness.