Effect of LH or HCG on Differentiation of Masculine Pattern of Gonadotropin Regulation in the Male Rat

抄録

Newborn male rats were injected with varying doses of LH or HCG from Day 1 (=the day of birth) to Day 2 and castrated on Day 3. At approximately 30 days of age they received subcutaneous ovarian transplantation. At autopsy on Day 60, ovarian grafts from saline controls contained numerous corpora lutea. Most of the saline-treated rats become “feminine males”. However, neonatal treatment with LH or HCG significantly reduced the incidence of “feminine males”. The minimal effective dose which is capable of masculinizing gonadotropin (GTH) regulation in a majority of rats seemed to exist between 1μg and 0.1μg for LH, and around 0.1 IU for HCG. Most of the rats receiving above the dose had a polyfollicular ovarian graft. These results suggest that if GTH level in the neonatal male rat is increased by injection of exogenous hormone the masculinization of GTH regulation is accelerated.