Renomedullary antihypertensive function in accelerated (malignant) XXXX . Observations on renomedullary interstitial cells.

@entity8 @entity95 @entity101
The antihypertensive function of the renal medulla was tested on accelerated (malignant) @entity101 of the @entity95 . A procedure for the development of accelerated @entity101 of the @entity95 of lethal proportions within 3 wk was established. This procedure consisted of the application of a rigid clip with a fixed and unyielding gap to the @entity8 . Three additional manipulations, other than simple nephrectomy, were performed on the right kidney after application of the rigid clip to the left renal artery. These were: (a) a sham operation, (b) @entity8 and its autotransplantation in a fragmented state, and (c) @entity8 and its autotransplantation in a fragmented state. After the sham-operated @entity8 , the standardized accelerated @entity101 did not develop, whereas after autotransplanted renal cortex it did. After a period of protection against accelerated @entity101 , removal of either the sham-operated kidney or the renomedullary transplants was followed by a prompt rise in arterial pressure and death of the animal. Thus, the antihypertensive action of renomedullary tissue was similar to that of the whole kidney. The main cell type noted in the protective renomedullary transplants had the microscopic characteristics of the lipid-containing interstitial cells. These cells occurred in clusters, often were near capillaries, and appeared hyperplastic. It is suggested that the renomedullary interstitial cell is the most eligible cell for exertion of the renomedullary antihypertensive action. Since vasoactive lipids are extractable from the renal medulla and its interstitial cells, the hypothesis that interstitial cells secrete antihypertensive substance(s) is attractive.
