An ultrastructural stereologic study of the effects of angiotensin II on the zona glomerulosa of rat adrenal cortex.

The effects of angiotensin II on the rat zona glomerulosa were investigated by morphometric and radio-immunological methods. Short-term (1 h) angiotensin-administration induced lipid depletion in zona glomerulosa cells and a significant rise in the plasma aldosterone concentration. Chronic angiotensin-treatment provoked a noticeable increase in the volume of the zona glomerulosa and its cells, which was mainly due to the hypertrophy of smooth endoplasmic reticulum and mitochondrial compartment. In chronically treated animals the output of aldosterone in response to a short-term stimulation with angiotensin II displayed a significant increase. These findings are interpreted as indicating that angiotensin II is involved in the stimulation of the growth and steroidogenic capacity of the rat zona glomerulosa.