[Human ontogeny of the hypothalamic neuroglandular system immunoreactive to an anti-hpGRF 44 immune serum]

An hypothalamo-infundibular neuroglandular system stained by an anti-hpGRF 44 serum is described in human brain. Perikarya are located in the infundibular nucleus, and their fibres end in posterior and lateral territories of the zona externa of the Median Eminence . Somatostatin fibres, morphologically different, also end in the same areas. Fibres giving intra- eminential terminals, so as hypothalamic perikarya are revealed as early as the 18 th week of fetal life.