[Histophysiological characteristics of the endocrine glands of the newborn infant].

Morphologic characteristics of endocrine glands in the perinatal period are considered, and the distinctive microstructural features found in many of them (adrenal cortex, thyroid, thymus, etc.) are interpreted in functional terms as being manifested in the cytolysis and resorption of hormone-producing elements. These processes reflect in turn the mobilization of emergency mechanisms of the endocrine system to meet the drastically increased requirements of the neonate for appropriate hormones under the conditions of stress experienced on transition from intrauterine to extrauterine existence. The nature of neonatal glandular atrophy and fibrosis is discussed, as is the question of morphologic classification of endocrine glands in general.