Adrenal Mitochondrial and Serum Corticosteroid Studies in RatsResistant to Adrenal-Regeneration Hypertension (ARH)

Abstract

Female rats of the Wistar-Furth (W/Fu) strain appear to be resistant to the development of adrenal regeneration hypertension. At a time period, after adrenal enucleation, when Holtzman female rats had elevated serum 11-deoxycorticosterone levels and were hypertensive, none of the W/Fu rats became hypertensive. In vitro adrenal studies after quiescent kills of W/Fu rats indicated that cholesterol side chain cleavage activity was greater in mitochondria from regenerating adrenals than from controls. Both serum deoxycorticosterone and corticosterone levels were significantly greater in the adrenal-enucleated group. These studies were repeated in animals which were given a standard ether anesthetic stress. Ether stress increased cholesterol side chain cleavage activity comparably in control and adrenal-enucleated rats and also increased their serum deoxycorticosterone and corticosterone levels. Adrenal-enucleated Wistar-Furth rats had higher serum deoxycorticosterone levels than controls, whereas controls had higher serum corticosterone levels than the adrenal-enucleated group after the ether stress. These results indicate that although the adrenal-enucleated W/Fu rats have increased serum deoxycorticosterone levels, none of these rats develop frank hypertension. This suggests a resistance to deoxycorticosterone-induced hypertension in this strain of rat.