The role of anabolic steroids on baseline and stress heart rate in cynomolgus monkeys

This investigation examined the role of anabolic steroids on baseline heart rate (HR) and HR responses to the threat of capture in Macaca fascicularis. Ten cynomolgus monkeys were randomly assigned either to a steroid or to a sham control group. Steroid-treated animals were given testosterone injections biweekly for 10 weeks, whereas sham controls received injections of sesame oil on an identical schedule. Pretreatment and posttreatment HRs were evaluated to establish both baseline and acute-stress responses. Results revealed that animals given testosterone experienced a statistically significant increase in baseline HR when contrasted with the sham controls. No difference between the groups was detected in response to the threat of capture.