EFFECTS OF PULSELESS PERFUSION ON DISTRIBUTION OF RENAL CORTICAL BLOOD-FLOW AND ON RENIN RELEASE

  • 1 January 1976
    • journal article
    • research article
    • Vol. 80  (1) , 31-39
Abstract
The effects of pulseless perfusion on the distrubution of renal blood flow and on release of renin were studied in anesthetized dogs. The distribution of renal blood flow to 4 cortical layers was determined with the radioactive microsphere technique during pulsatile control conditions and after 1 and 2 h of pulseless perfusion, without significant changes in mean arterial pressure and mean total renal blood flow. Simultaneously, renal vein blood samples were analyzed for renin (radioimmunoassay technique. During pulseless perfusion there was a consistent and progressive redistribution of blood flow toward deeper cortical layers with the outer cortical layer falling from 36.9 to 25.3% (P < 0.001) and the juxtamedullary cortex increasing from 14.5 to 25.4% (P < 0.001) after 2 h. There was also a progressive increase in renal venous concentration of renin, which was 20.91 .+-. 6.6 ng./m per h after 2 h of pulseless flow compared to 5.06 .+-. 1.16 ng./mm per h during control conditions (P < 0.05). These changes in cortical blood flow and in release of renin were not observed in sham-operated controls. Pulseless flow alone produced a significant increase in renal production of renin and a significant redistribution of renal cortical blood flow, due to the greater vasoconstriction in the outer cortex when compared to the juxtamedullary cortex.