Anabolic androgenic steroids and aggression: studies using animal models.

The use of anabolic androgenic steroids (AASs) has escalated in teenagers and is associated with increased violence. Adolescent exposure to chronic high levels of AASs is of particular concern because puberty is a hormonally sensitive period during which neural circuitry for adult male patterns of behavior develop. Thus, teenage AAS use may have long-term repercussions on the potential for displaying aggression and violence. Animal models have contributed valuable information on the effects of AAS use. For example, studies in rodents confirmed that exposure to the AASs testosterone and nandrolone, but not stanozolol, does indeed increase aggression. A side effect of AAS use reported in humans is "'roid rage," characterized by indiscriminate and unprovoked aggression. Results of animal studies demonstrated that pubertal rats receiving AASs respond appropriately to social cues as they are more aggressive toward intact males than are castrates. Also, testosterone-treated males recognize appropriate environmental cues as they are most aggressive in their home cage. Thus, adolescent AAS exposure increases aggressive behaviors, but does not induce indiscriminate aggression. To assess whether AAS exposure increases aggression after provocation, rats were tested following a mild tail-pinch. In adolescent males, provocation increased aggression after withdrawal from testosterone, nandrolone, and stanozolol, an effect which persisted for many weeks. The data suggest that AASs sensitize animals to their surroundings and lower the threshold to respond to provocation with aggression. Thus, in humans, pubertal AAS exposure may not cause violent behaviors, but may increase the likelihood that aggressive acts will result in violence. This may persist into adulthood.