During midgestation, the fetal zone occupies 80–90% of the cortical volume and produces 100–200 mg/day of the androgenic C 19 steroid, dehydroepiandrosterone sulfate (DHEA-S), which is quantitatively the principal steroid product of the primate fetal adrenal gland throughout gestation. As its name implies, the fetal zone exists only during fetal life it atrophies soon after birth and has no counterpart postnatally. During the latter two thirds of gestation in humans and higher primates, the fetal adrenal glands are disproportionately enlarged and exhibit extraordinary growth and steroidogenic activity in a specialized cortical compartment known as the fetal zone ( 4– 7). production of glucocorticoids and mineralocorticoids, and to ensure adrenal cortical autonomy once the placenta has separated.ĭevelopment and function of the primate fetal adrenal cortex are distinct from those in other species. Moreover, the fetal adrenal cortex must itself undergo maturational changes in preparation for its essential role postnatally, i.e.
Appropriate development and function of the fetal adrenal cortex therefore are critical for fetal maturation and perinatal survival. STEROID hormones produced by the fetal adrenal cortex regulate intrauterine homeostasis, the maturation of fetal organ systems necessary for extrauterine life, and, in some species, the timing of parturition (Refs. Timing of parturition and fetal maturation Indirect effect of placental glucocorticoid metabolismī. Nuclear receptors/transcription factorsģ. Insulin-like growth factors I and II (IGF-I and IGF-II)Ĭ. Functional zonation and ontogeny of steroidogenic enzyme expressionģ.
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