Background Accumulating clinical and epidemiological evidence suggests significant
gender differences in the incidence of and outcome following major infection. In a rodent
model of hemorrhagic shock, investigators have shown that males manifest depressed cell-
mediated immunity that is reversed by castration or pharmacologic testosterone receptor
blockade. Female rats, in contrast, show enhanced immune function that is reduced to male
levels by testosterone administration. This sexual dimorphism is believed responsible for the …