EFFECTS OF SODIUM REPLETION AND TIMOLOL MALEATE ADMINISTRATION ON THE ZONA GLOMERULOSA OF THE RAT ADRENAL-CORTEX - AN ELECTRON-MICROSCOPIC MORPHOMETRIC STUDY

  • 1 January 1982
    • journal article
    • research article
    • Vol. 79  (1) , 81-88
Abstract
The effects of long-term Na repletion and timolol maleate treatment on the zona glomerulosa of dexamethasone- and ACTH-administered rats were investigated. Morphometry showed that both treatments induced a noticeable atrophy of the zona glomerulosa and its parenchymal cells, which is mainly due to the decrease in the smooth endoplasmic reticulum and the mitochondrial compartment. Radioimmunological studies indicated that in the treated rats the plasma aldosterone concentration was significantly decreased. Combined Na repletion and timolol maleate administration provoked more intense effects than the single treatments. Both Na/K balance and the renin-angiotensin system apparently are involved in the maintenance of the growth and steroidogenic capacity of the rat zona glomerulosa, without interfering with the hypothalamo-hypophyseal-adrenal axis.