Effects of prostaglandin E2 and I2 on renal cortical and medullary blood flow in rabbits.
The effects of intra-aortic administrations of prostaglandin (PG) E2 and I2 on the renal regional blood flow were investigated in rabbits. Mean arterial blood pressure (MABP) was monitored by the direct method and total renal blood flow (TRBF) was measured using the electromagnetic method. Renal cortical and medullary blood flows (RCBF and RMBF) were measured by the hydrogen gas clearance method. Both PGE2 and PGI2 caused a dose-dependent reduction of MABP. At doses having no significant effect on MABP, PGE2, and PGI2 increased TRBF and decreased renal vascular resistance (RVR). The maximum reduction in RVR induced by PGI2 was significantly greater than that by PGE2. PGE2, produced significant increases in RCBF and in particular in RMBF, while PGI2 induced similar changes in RCBF and RMBF. The results suggest that PGE2, which is a weaker vasodilator than PGI2, mainly acts as a medullary vasodilator, and that PGI2 has similar vasodilatory effects on the cortex and medulla.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D015232:Dinoprostone; D011464:Epoprostenol / Q000494:pharmacology*; D066298:In Vitro Techniques; D007672:Kidney Cortex / Q000098:blood supply*; D007679:Kidney Medulla / Q000098:blood supply*; D008297:Male; D011458:Prostaglandins E / Q000494:pharmacology*; D011817:Rabbits; D012039:Regional Blood Flow / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects
D011458:Prostaglandins E; D011464:Epoprostenol; D015232:Dinoprostone