Low arginine plasma levels do not aggravate renal blood flow after experimental renal ischaemia/reperfusion

Background: ischaemic renal dysfunction is present in many clinical setting s, including cardiovascular surgery. Renal hypoperfusion seems to be the mo st important pathophysiologic mechanism. Arginine plasma levels are rate li miting for NO synthesis, and low arginine plasma levels are seen after majo r vascular surgery. Objective: to establish the effects of low arginine plasma levels oil renal blood flow after renal ischaemis/reperfusion. Design: Wistar rats were used in this unilateral renal ischaemia/reperfusio n model. After 70 min of ischaemia, the kidney was reperfused for 150 min, Arginase infusion was used to lower arginine plasma levels. Blood flow meas urement was performed at the end of the experiment using radiolabelled micr ospheres. Additional experiments were performed for histopathology. Results: arginase efficiently decreased arginine plasma levels to about 50% of normal. There was a lower blood flow, hl the ischaemic kidney than the contralateral (non-ischaemic) kidney. Lowering arginine plasma levels did n ot reduce renal blood flow in the ischaemic kidney. Renal histopathology wa s not influenced by lowered arginine plasma levels. Conclusions: lowering arginine plasma levels did not affect blood flow or h istology following renal ischaemia and reperfusion.