THE EFFECTS OF SERTRALINE ON NICOTINE SELF-ADMINISTRATION AND FOOD-MAINTAINED RESPONDING IN SQUIRREL-MONKEYS

Recent reports suggested the involvement of serotonergic mechanisms in nicotine self-administration. The present study assessed the effects of sertraline, a selective serotonergic uptake inhibitor, on the reinf orcing effects of i.v. nicotine (30 mu g/kg per injection) in squirrel monkeys responding under a fixed-ratio schedule. Nicotine (10-100 mu g/kg per injection) produced a significant inverted U-shaped distribut ion on FR rate. Vehicle or sertraline (3, 6, 12, 24 mg/kg, p.o.) produ ced no changes in the response rates maintained by 30 mu g/kg per inje ction i.v. nicotine, but sertraline produced non-significant increases response rates maintained by 10 mu g/kg per injection nicotine and ve hicle. In a separate group of monkeys, sertraline given in combination with i.m. doses of nicotine produced a significant dose-dependent dec rease in responding maintained by food-pellet delivery. Thus, sertrali ne produced differential effects on response rates that may be related to (1) route of nicotine administration and (2) whether the behavior was maintained by nicotine or food. In addition, the results of the se lf-administration study suggest that sertraline would not disrupt well -maintained responding for nicotine.