Localization of alkaline and acid phosphatases in healthy human adrenal cortex. Light and electron microscopic study.

Localization of alkaline and acid phosphatase activity was investigated in healthy human adrenal cortex by light and electron microscopy. The activity of both was found in the inner part of the adrenal cortex--mainly in the reticular zone. The reaction products of alkaline phosphatase were observed along the plasma membrane and those of acid phosphatase were observed mainly in the lysosomes and secretory vacuoles. The heavier deposit of phosphatase reaction products in the reticular zone may be explained by the fact that the reticular zone is most active in the steroidogenesis of glucocorticoid and adrenal androgen.