Effects of methamphetamine on sexual performance and compulsive sex behavior in male rats

Methamphetamine (Meth) is a highly addictive psychostimulant associated with enhanced sexual desire, arousal, and sexual pleasure. Moreover, Meth abuse is frequently linked with the practice of sexual risk behavior and increased prevalence of human immunodeficiency virus. Currently, there is a lack of studies investigating the effects of Meth on maladaptive sexual behavior under controlled experimental settings in animal studies. The overall objective of the current study was to examine the effects of Meth on various aspects of male sexual behavior including maladaptive sex-seeking behavior. First, a dose-response curve of the effects of Meth (0, 1, 2, and 4 mg/kg; s.c.) on sexual motivation and performance was conducted in sexually na < ve and experienced male rats. Next, the effects of Meth (1 mg/kg; s.c.) on inhibition of maladaptive sexual behavior was tested using a sex aversion conditioning paradigm, in which visceral illness induced by lithium chloride (LiCl) was paired with sexual behavior. Meth administration inhibited sexual performance in a dose-dependent matter as evidenced by the decreased percentages of males that mated and increased latencies to initiate sexual behavior when injected with 2 or 4 mg/kg Meth. Moreover, an acute dose of Meth prior to or following sex aversion conditioning resulted in disrupted conditioned inhibition of sexual behavior. These data suggest that Meth administration in male rats impairs sexual motivation and performance. In addition, low doses of Meth that do not disrupt sexual function may result in maladaptive seeking of sexual behavior.