Glomerular hemodynamics during abortion induced by RU 486 and sepsis in rats

1. Acute renal failure is a very common consequence of septic abortion. Whole kidney and glomerular hemodynamics were evaluated in virgin (V), pregnant (PREG) and aborted (ABOR) euvolemic Munich-Wistar rats before and after E. coli (0111-B4) endotoxin (LPS) infusion in order to evaluate the effect of septic abortion on the renal microcirculation. 2. Abortion induced by RU 486 blunted the increase in glomerular filtration rate (GFR) induced by normal pregnancy (0.86 +/- 0.03 vs 0.63 +/- 0.07 ml/min, P < 0.05). In virgin rats, RU 486 did not modify the parameters of renal function. Significant alterations occurred in whole kidney and single nephron function. However, the changes in whole kidney function in the ABOR group were significantly higher than those observed for the V group (reductions in GFR were 42% in V and 80% in ABOR, RPF decreased 34% in V and 76% in ABOR, TRVR increased 82% in V and 400% in ABOR). 3. Mean single nephron glomerular filtration rate (SNGFR) was reduced in all groups after LPS (44% in V, 43% in V+RU, 55% in PREG, 60% in ABOR), due to significant decreases in glomerular plasma flow rate, QA (42% in V, 55% in V+RU, 53% in PREG, 57% in ABOR) and in glomerular ultrafiltration coefficient, Kf (46% in V, 47% in V+RU, 45% in PREG, 67% in ABOR). 4. These data show that LPS induced significant alterations in renal function in all groups. However, aborted rats were more sensitive to the effects of LPS than V rats. These results indicate that abortion may potentiate the effects of endotoxemia on renal function elevating the extent of acute renal failure and thus the mortality rate.