Stimulation of LH Release in Men and Women by LH-Releasing Hormone Purified from Porcine Hypothalami

Abstract

LH-releasing hormone (LRH2), purified from porcine hypothalamic tissue, was tested in the human being. The LRH was injected iv into the following 8 subjects: 2 untreated men, 2 untreated women, 2 men pretreated with ethinyl estradiol, and 2 women pretreated with an oral contraceptive preparation (Lyndiol). The design was that of a 4-factor partially nested factorial experiment in which serum LH and FSH levels were measured by specific radioimmunoassays and compared with the values obtained after injection of a control solution of lysine vasopressin. The data indicated a highly significant increase (p <0.01) in serum LH at 23.5 min and a significant increase (p <0.05) in serum FSH at 24.5 min after administration of LRH. There was a 3.7-fold mean increase in serum LH levels with a range of 1.9–7.5, and a 2.2-fold mean increase in serum FSH levels (1.2–4.8). The response to LRH was not significantly influenced by either the sex of the subject or pretreatment with a steroid suppressing LH release. This study demonstrates that administration of LRH of porcine origin can induce release of LH in both men and women and thus is not species specific.