Light and electron microscopic immunocytochemistry on the localization of 3 beta-hydroxysteroid dehydrogenase/isomerase in the bovine adrenal cortical cells.

The localization of 3 beta-hydroxysteroid dehydrogenase/isomerase (3 beta-HSD) was studied in bovine adrenal glands by light as well as electron microscopic immunocytochemistry, using anti-bovine adrenal 3 beta-HSD antibody. With light microscopy the cytoplasm of the glomerulosa cells was weakly immunostained, while that of the fasciculata-reticularis cells was intensely immunostained though both the capsular connective tissue cells and the medullary cells were entirely negative for this reaction. Electron microscopic immunocytochemistry revealed that the positive reaction products for 3 beta-HSD were present on the membrane of smooth endoplasmic reticulum of the cortical cells, especially that of the fasciculata and reticularis cells. Other cell organelles such as mitochondria and Golgi apparatus were entirely negative. The present results indicate that 3 beta-HSD is present in the membrane of smooth endoplasmic reticulum of bovine adrenal cortical cells.