It's fairly well established that a symptom of heat-stroke can be aggression. I haven't found anything that indicates whether this is directly related to testosterone levels. On the other hand, I do see things about testosterone levels that further suggest the stress/aggression correlation, for instance a popularization here.
In this article about aggression, we see
A disturbance in the body's chemistry or physiology - perhaps brought on by fatigue, hunger or lack of sleep - may alter a person's self-control. Medical conditions can sometimes play a role, eg a person taking medication for diabetes may develop low blood sugar (hypoglycaemia) if they miss a meal and can become aggressive as a result.Well, that seems in line. Then there is the chicken and egg argument -- which comes first, the testosterone or the aggression? Discussed here, with related articles.
Also, this, and this somewhat dubious page :-) on wiki.