Portions of female guinea pig copulatory patterns in natural or induced estrous are known to resemble mounting of the sexually active male. It has also been demonstrated that anestrous females may be induced to mount due to testosterone propionate. This study was to test androgen synergy and antagonism with estrogen and progesterone in inducing mounting patters in ovariectomized females.
Treatment groups were: (1) oil injected controls, (2) estrogen and progesterone treated females, (3) daily testosterone treated females (1 mg/day), and (4) daily testosterone treated females given estrogen and progesterone. Animals were observed continuously and simultaneously for twelve hours every two weeks following the progesterone injection of the standard four day estrogen-progesterone sequence for estrous induction. Seven test sessions were conducted.
Mounting was observed a mean of 20.5 times in the estrogen and progesterone group, 4.2 times in the testosterone treated group, 1.2 times in the combined treatment group, and .07 times in control group. Estrous behavior manifest by lordosis was demonstrated in 75% of the animal-tests for the estrogen and progesterone group and less than 1% for the other groups.
The nervous tissues in the female which mediate mounting activity, usually considered a male behavior component, normally respond and are much more sensitive to female hormones than to androgens. Further, androgen treatment may antagonize the normal mounting pattern rather than augment it.