Sexual Behavior in Normal and Prenatally Androgenized Female Hamsters

It has been argued that testosterone exposure is necessary for the development of male sexual behavior patterns. Normal female hamsters, unlike female rats, have been rarely observed to display male sexual behavior. The ability of female rats to display male sexual behavior is attributed to prenatal exposure to testosterone which is secreted by their male sibling. Since hamsters have a shorter gestation period, it has been argued that, therefore, female hamsters do not have a chance for prenatal androgen exposure so that they lack the ability to display male sexual behavior. However, long term gonadal hormone treatments during adulthood do induce male sexual behavior in female hamsters. This suggests that organizational effects of gonadal hormones could occur during adulthood. To test whether adult hormonal treatments are organizational or activational, this study tried to clarify whether male sexual behavior patterns exist in normal female hamsters free of any exogenous androgen treatments. When simply pairing the experimental female hamsters with estrous stimulus female hamsters (Mesocricetus auratus), 26 of 38 normal female hamsters displayed thrusts at least once over 8 estrous cycles. Therefore, the effects of hormonal treatments during adulthood appear activational rather than organizational. To examine whether these male sexual behavior patterns developed as a result of prenatal androgen actions, testosterone propionate injections to the pregnant hamsters during the last three days of gestation period (2 or 4 mg per day) produced female hamster offspring (n = 34) which showed augmented male sexual behavior without decrement in lordosis. It was also found that the male sexual behavior of both normal and prenatally androgenized female hamsters was activated by progesterone. The latter result provided a paradoxical case for the conventional dichotomy of the organizational effects: masculinization versus defeminization.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Psychology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Hsu, Chia-Hung

• Education, Educational Psychology

Identifier

(UMI)AAI8302888

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/69616