Neuropharmacology: Nicotine withdrawal in the rat: role of alpha7 nicotinic receptors in the ventral tegmental area

CACorresponding Author PREVIOUS data show that nicotinic receptors in the ventral tegmental area are of importance for the nicotine withdrawal syndrome. Here we have investigated the speci®c role of á7 nicotinic receptors in the ventral tegmental area for the neurobiological and behavioral consequences of nicotine withdrawal. Rats were exposed to nicotine for 14 days via s.c. osmotic minipumps. Bilateral intrategmental injections of the selective á7 nicotinic receptor antagonist methyllycaconitine reduced locomotion in the nicotine-treated rats, but not in control animals. Unilateral intrategmental injection of methyllycaconitine reduced dopamine output in the ipsilateral nucleus accumbens of nicotinetreated rats, but not in controls. Our results indicate that á7 nicotinic receptors in the ventral tegmental area are involved in the nicotine withdrawal syndrome. NeuroReport 10:697±702 # 1999 Lippincott Williams & Wilkins.