Nitric oxide mediates mecamylamine- and naloxone-precipitated nicotine withdrawal.

A nitric oxide synthase inhibitor blocked nicotine abstinence signs and increased weight loss in male, nicotine-dependent rats during withdrawal precipitated by the nicotinic receptor antagonist mecamylamine or the opioid receptor antagonist naloxone. These results indicate that nitric oxide systems mediate important aspects of the expression of nicotine physical dependence and suggest the potential use of nitric oxide synthase inhibitors as aids in tobacco smoking cessation.