Socially stimulated androgen surges in male hamsters: the roles of vaginal secretions, behavioral interactions, and housing conditions.

The sources of cues necessary for elicitation of androgen surges and sexual behavior in male golden hamsters (Mesocricetus auratus) were investigated. Circulating androgen levels were measured in males after interactions with other males or several types of estrous females: intact females, vaginectomized females, or vaginectomized females scented with vaginal secretions. All groups of males that interacted with estrous females demonstrated significant elevations in androgens whereas those that interacted with other males did not. Thus, the presence of vaginal secretions is not necessary for the elicitation of androgen surges in sexually experienced male hamsters. Individual differences in sexual performance were not correlated with the degree of change in androgen levels, suggesting that such hormonal responses are not graded but are all-or-none. Housing males in isolation from females did not alter either baseline androgen levels or the magnitude of androgen responses caused by interactions with females.