Enzyme histocytochemical studies in human adrenocortical adenomas. [I]. Primary aldosteronism.

Enzyme histocytochemical staining including alkaline phosphatase, acid phosphatase, 3 beta hydroxysteroid dehydrogenase and 11 beta hydroxysteroid dehydrogenase was studied in human adrenocortical adenomas associated with primary aldosteronism. Histochemically, these enzyme activities were weaker in clear cell type adenomas than in the normal human adrenal cortex. While compact cell type adenomas showed stronger enzyme activities than the clear cell type adenomas. Electron microscopic localization of alkaline phosphatase was mainly observed in plasma membrane at the intercellular sites. Occasionally, this enzyme activity was also observed in the mitochondrial outer membrane, mainly in compact cells. The significance of these enzymes in the adenoma cells is discussed.