Effects of Prolactin on the Sensitivity of the Testis to LH1

Abstract

Treatment of adult hypophysectomized rats with ectopic pituitary homografts caused a significant increase in testicular sensitivity to LH, as determined from measurements of peripheral testosterone levels 2.5 h after the injection of a single large dose of LH. Increased testicular responsiveness to acute LH stimulation was also observed after treatment with grafts or prolactin (PRL) combined with a chronic LH treatment, and in some instances, after treatment with PRL or chronic LH alone. It is suggested that PRL may have a role in sensitizing the testis to LH in the course of normal sexual maturation.