RENAL VASOCONSTRICTIVE RESPONSE TO CONTRAST-MEDIUM - THE ROLE OF SODIUM-BALANCE AND THE RENIN-ANGIOTENSIN SYSTEM

Google Scholar
  • 1 January 1983
    • journal article
    • research article
    • Vol. 101  (3) , 385-391
Abstract
Injection of contrast medium into the renal artery causes a biphasic change in renal blood flow, a transient vasodilation followed by a more prolonged vasoconstrictive phase. The role of Na+ balance in the vasoconstrictive response to contrast medium was evaluated in Na+-deplete dogs (n = 5) and Na+-replete dogs (n = 5). Contrast medium, 2 ml diatrizoate solution/4 s, was injected into the renal artery in anesthetized dogs. Renal blood flow was 117 .+-. 25 ml/min and 173 .+-. 12 in the Na+-deplete and Na+-replete dogs, respectively. After the injection of contrast medium and following the transient vasodilation phase, renal blood flow significantly decreased from baseline by 42.2 .+-. 4.2 and 12.2 .+-. 11.% in Na+-deplete and Na+-replete dogs, respectively. The duration of the vasoconstriction phase was significantly prolonged in the Na+-deplete dogs, 343 .+-. 27 s vs. 147 .+-. 48 in Na+-replete dogs. Blockade of the intrarenal renin-angiotensin system with the renal artery infusion of Sar1-Ala8-All [angiotensin II] (50 .mu.g/kg per min) did not significantly alter the magnitude of vasoconstrictive response to contrast medium in Na+-deplete animals, but the duration of the vasoconstrictive phase was decreased from 277 .+-. 59 s to 86 .+-. 13. Evidently, Na+ depletion accentuates both the magnitude and duration of the vasoconstrictive phase of the renal blood flow response to injection of contrast medium and blockade of the intrarenal renin-angiotensin shortens the duration of this response.

This publication has 2 references indexed in Scilit: