Endothelial vasoconstrictor prostanoids, vascular reactivity, and acute renal failure

The interaction of endothelium-derived vasoconstrictor prostaglandins, the angiotensins (Ang), and the sympathetic nervous system in acute renal failure still remains to be determined. In this study; acute renal failure (ARF) was induced in male Wistar Kyoto rats (N = 7) in a 2K/2C model of 30-minute clamping. Contractions to Ang I and II and norepinephrine (NE) were studied in isolated aortic and renal artery rings 24 hours after clamp release. Sham-operated animals served as controls (N = 7). In ARF, contractions to NE were increased in the aorta and even further enhanced in the renal artery (P < 0.05 to 0.001), whereas contractions to Ang I and II were blunted (P < 0.05). Contractions were inhibited by SQ 30741, a thromboxane A(2) (TXA(2))/prostaglandin H-2 (PGH(2)) receptor antagonist. We conclude that ARF is characterized by abnormal vascular reactivity both in the renal as well as the systemic vasculature that is in part mediated by endothelium-derived vasoconstrictor prostaglandins.