[Effects of chronic surfagon administration on secretion of luteinizing hormone and morphofunctional state of the testes in Papio hamadryas].

The paper is concerned with the results of a study of the effects of chronic (12 weeks) subcutaneous infusion of surfagon (D-Ala6, des-Gly10-ethylamide of LH-RH, a daily dose of 3 micrograms/kg of body mass) using osmotic mini-pumps on hormonal function of the hypophyseogonadal system, spermatogenesis and testicular histology in experiments on Papio Hamadryas. Prolonged infusion of surfagon through short-term transient activation of the hypophyseogonadal system was shown to cause inhibition of the basal secretion of LH-RH and testosterone, induction of hypophyseal desensitization to native LH-RH, development of oligo- and azospermia. Inhibited function of the testes was accompanied by noticeable changes in their histological structure (suppression of germinative cell division, narrowing of the seminiferous tubules, moderately transient fibrosis of connective stroma). Neither focal block of spermatogenesis nor foci of calcification or necrosis (observed in rats subjected to prolonged infusion of LH-RH agonists) were observed in Papio Hamadryas. All changes in the reproductive system (including gonadal histology), induced by chronic infusion of surfagon, were of reversible nature.