Effects of pyridoxalated hemoglobin polyoxyethylene conjugate(PHP) on renal circulation in isolated perfused rat kidneys.

We examined effects of perfusion of the kidney with pyridoxalated hemoglobin polyoxyethylene conjugate(PHP) solution on rat renal vascular responsiveness to norepinephrine(NE), angiotensin-II (AN-II), acethylcholine(ACh) and nitroglycerine(NG). The rat kidney was perfused with hydroxyethylstarch(HES) or PHP at a constant flow rate, using a pump. Perfusion pressure was monitored by a pressure transducer. Changes in PP induced by NE, AN-II, ACh and NG was examined. NE and AN-II applied intra-arterially induced a dose-related increase in PP in rat kidney perfused with both HES and PHP perfused groups. ACh and NG produced a dose dependent decrease in PP in both HES and PHP-perfused groups. There was no significant difference in response to ACh and NG between both groups. Results suggests that in rat vascular beds, PHP dose not interfere vascular relaxation caused by release of EDRF induced by ACh.