Prenatally injected testosterone propionate and sexual behavior of female rats

Abstract

Female rats were exposed to oil or to testosterone propionate (TP) on Day 16 or Day 19 of gestation via injection into pregnant females. On Day 1 or Day 5 after birth, subgroups of these animals were injected with oil or TP. In adulthood, the external genital morphology, functional state of ovaries, and the display of feminine and masculine sexual behavior in response to exogenous hormones were examined. A high percentage of females exposed to TP on Day 19 of gestation had modified vaginas whereas other prenatally treated groups had normal genitalia. Prenatal treatment with TP alone did not appear to disrupt ovarian function since corpora lutea (CL) were present at approximately four months of age. However, injection of 1 μg TP on Days 1 or 5 postnatally did prevent the formation of CL across all prenatal treatment groups. Females exposed to TP on Day 19 of gestation exhibited deficits in feminine sexual behavior when compared to controls or females exposed to TP on Day 16 of gestation. The data support the concept of a discrete prenatal period during which circulating androgen influences the development of tissues which mediate feminine sexual behavior in the rat.