Both nicotine reward and withdrawal are enhanced in a rodent model of diabetes.

Abstract

It is presently unclear whether diabetic rats experience greater rewarding effects of nicotine and/or negative affective states produced by nicotine withdrawal. The present study utilized a rodent model of diabetes to examine the rewarding effects of nicotine and negative affective states and physical signs produced by withdrawal. Separate groups of rats received systemic administration of either vehicle or streptozotocin (STZ), which destroys insulin-producing beta cells in the pancreas and elevates glucose levels. Place conditioning procedures were utilized to compare the rewarding effects of nicotine (conditioned place preference; CPP) and negative affective states produced by withdrawal (conditioned place aversion; CPA) in vehicle- and STZ-treated rats. CPA and physical signs of withdrawal were compared after administration of the nicotinic receptor antagonist mecamylamine to precipitate withdrawal in nicotine-dependent rats. A subsequent study utilized elevated plus maze (EPM) procedures to compare anxiety-like behavior produced by nicotine withdrawal in vehicle- and STZ-treated rats. STZ-treated rats displayed greater rewarding effects of nicotine and a larger magnitude of aversive effects and physical signs produced by withdrawal as compared to vehicle-treated controls. STZ-treated rats also displayed higher levels of anxiety-like behavior on the EPM during nicotine withdrawal as compared to controls. The finding that both nicotine reward and withdrawal are enhanced in a rodent model of diabetes implies that the strong behavioral effects of nicotine promote tobacco use in persons with metabolic disorders, such as diabetes.