Anabolic-androgenic steroids: effects on social behavior and baseline heart rate

Examined the effects of anabolic-androgenic steroids (AS) on behavior, baseline heart rate (HR), and stress-induced HR responses. Twenty-four cynomolgus monkeys were assigned to four mixed social groups of both AS and sham control animals. For 2 months, AS-treated monkeys received biweekly injections of testosterone, and, on an identical schedule, the control animals were injected with a sham solution. Behavioral data revealed that AS disrupted the social milieu such that all dominant animals exhibited increases in dominant behavior and subordinates manifested increased submission. These changes returned to pretest levels 8 weeks following termination of the drug intervention. Affiliative behaviors decreased on the part of all animals as a function of AS and, with the exception of play behavior, failed to return to pretest levels after the 8-week period of recovery. AS created an increase in baseline HR, particularly among the dominant animals. Interestingly, the subordinate AS animals experienced a decrease in baseline HR response. AS had no apparent influence on stress-induced HR reactivity.