Renal function in the fetal lamb: a chronic model to study physiological effects of ureteral ligation and deligation

Between 53 and 98 days of gestation 11 fetal lambs were subjected to unilateral ureteral ligation. In 8 fetuses re-exploration was performed 35 to 41 days after ligation. Chronic catheterization of the obstructed kidney, bladder and fetal vascular system was used for analysis of physiological data. Average creatinine clearance was 1.35 +/- 0.067 ml. per minute in the control kidney and 0.226 +/- 0.057 ml. per minute in the obstructed kidney after diversion. Free water clearance, osmolar clearance and fractional sodium excretions were not statistically significantly different in control and obstructed kidneys.