Changes in the morphology and location of arterial lesions in virgin and breeder Sprague-Dawley and spontaneously hypertensive rats (SHR) to adrenal regeneration hypertension.

Repeatedly bred, spontaneously hypertensive rats (SHR), unlike breeder Sprague-Dawley (S-D) rats, develop intimal hyalin lesions of the small sized gonadal arteries exclusively. When subjected to adrenal regeneration hypertension (ARH), breeder SHR develop aortic sclerosis identical to the arteriosclerosis which appears in breeder S-D rats. virgin and breeder S-D and SHR were subjected to ARH and were killed 8 weeks later. ARH caused a much greater increase in the blood pressure of S-D than in SH rats. Circulating levels of aldosterone, deoxycorticosterone, and corticosterone were significantly lower in the ARH-treated S-D and SH rats. The regenerated adrenal cortices of the S-D rats manifested extensive lipid depletion indicative of active synthesis and discharge; the regenerated cortices of SHR were replete with lipid suggestive of depressed steroidogenesis. The diverse morphology and anatomical location of arterial lesions in virgin vs breeder SR may be related to adrenal steroidogenesis.