EFFECTS OF ENDOTHELIN AND ANGIOTENSIN-II ON RENAL HEMODYNAMICS IN EXPERIMENTAL MESANGIAL PROLIFERATIVE NEPHRITIS

The renal hemodynamic response to pressor substances in the diseased k idney has been suggested to be different from that in the normal kidne y. The aim of this study was to investigate the effects of endothelin and angiotensin II on renal hemodynamics in experimental nephritis ind uced by the administration of antithymocyte serum in Wistar rats. This model showed mesangiolytic lesions in the glomeruli on day 2 and hype rcellular lesions on day 8. Prior to the injection of either endotheli n or angotensin II, the glomerular filtration rate and renal plasma fl ow were significantly lower in model rats on day 2 or day 8 than in th e control rats. The basal glomerular filtration rate and renal plasma flow on day 8 were negatively correlated with the mesangium cell numbe r. The injection of endothelin (0.5 ng/kg BW) led to a decrease in bot h renal plasma flow and glomerular filtration rate in rats on day 8 wh ich was significantly greater than that in the control rats. Similarly , angiotensin II infusion (0.2 mug/kg BW) reduced both renal plasma fl ow and glomerular filtration rate in the rats on day 8 and the reducti ons were significantly greater than those in the control rats. In conc lusion, renal hemodynamics in rats with mesangial proliferation of the kidney were more sensitive to both endothelin and angiotensin II than those in the normal kidney.