Inhibition of prostaglandin and nitric oxide synthesis prevents cortisol-induced renal vasodilatation in sheep

R. De Matteo, C. N. May

Research output: Contribution to journalArticleResearchpeer-review

27 Citations (Scopus)

Abstract

Glucocorticoids increase renal blood flow (RBF) and glomerular filtration rate in many species, but the mechanisms involved are unclear. We investigated whether cortisol-induced renal vasodilatation in conscious sheep depends on interactions with prostaglandins or angiotensin II. Intravenous infusion of cortisol (5 mg/h) for 5 h increased renal conductance (RC) by 1.06 ± 0.24 ml · min-1 · mmHg-1 more than vehicle. During intrarenal infusion of indomethacin (0.25 mg · kg-1 · h-1), the cortisol-induced increase in RC (0.28 ± 0.21 ml · min-1 · mmHg-1) was significantly reduced. The cortisol-induced rise in RBF (103 ± 17 ml/min) was not significantly reduced by indomethacin treatment (76 ± 9 ml/min). Combined intrarenal infusion of indomethacin (0.25 mg · kg-1 · h-1) with N(ω)- nitro-L-arginine (2.0 mg · kg-1 · h-1), a nitric oxide synthase inhibitor, abolished the cortisol-induced increases in both RC and RBF. Inhibition of angiotensin II synthesis with intravenous captopril (40 mg/h) blocked the renal vasoconstrictor action of angiotensin I but did not inhibit the cortisol-induced increases in RBF and RC. This study provides evidence that nitric oxide and prostaglandins play a role in cortisol-induced renal vasodilatation but indicates that this response is independent of an interaction with angiotensin.

Original languageEnglish
JournalAmerican Journal of Physiology - Regulatory Integrative and Comparative Physiology
Volume276
Issue number4 45-4
Publication statusPublished - 1 Apr 1999
Externally publishedYes

Keywords

  • Angiotensin
  • Indomethacin

Cite this