Dehydroepiandrosterone sulfotransferase localization in human adrenal glands: a light and electron microscopic study

Dehydroepiandrosterone sulfate is the major secretory product of the human adrenal cortex. The enzyme responsible for the sulfurylation, which has been isolated previously, possesses kinetic properties suggesting that it plays an important regulatory role in dehydroepiandrosterone sulfate secretion. In order to study the localization of the enzyme in the respective zones and cells of the cortex, an antibody to the pure enzyme was raised and the immunoglobulin G fraction employed in the peroxidase-antiperoxidase method. Staining was confined to the zona reticularis but was unevenly distributed throughout the cells. Electron microscopic examination of sections prepared from fresh adrenal tissue fixed in glutaraldehyde, revealed that the enzyme was predominantly clustered around lipid droplets. It is suggested that this may reflect an association of organelles, cholesterol being transported from lipid droplets to surrounding mitochondria, and pregnenolone then being converted to dehydroepiandrosterone in the adjacent endoplasmic reticulum and thence immediately sulfurylated.