Role de la glande pineale dans la regulation de l’axe hypothalamo-hypophyso-testiculaire

Abstract

THE ROLE OF THE PINEAL GLAND IN THE REGULATION OF THE HYPOTHALAMO-PITUITARY-TESTI-CULAR AXIS. The role of the pineal gland and of its main hormone, melatonin, has not yet been clearly defined. The best known activity of the gland is antigonadal, at least in the experimental animals. In fact, the administration of melatonin or the modification of the light/darkness ratio, that is considered the most important regulatory mechanism of the melatonin-synthetic activity, leads to a gonadal regression by which all the morphological and hormonal parameters are modified. Such a mechanism is not operating in humans. However, data exist indicating a role for the pineal in this species. Our experimental data and those of the litterature indicate that the action of melatonin seems to be principally at the hypothalamic level, even though a direct action at the pituitary and gonadal levels cannot be excluded.