Experimental obstructive hydronephrosis in newborn rats. I. Surgical technique and long-term morphologic effects.

Partial obstruction of one ureter was created in newborn rats and its effects were studied in the adult rat. The obstructed renal pelvis was found to be enlarged 10x. The parenchymal weight of this kidney was reduced by 8 per cent, primarily because of destruction of the papilla, and was completely compensated for by hypertrophy of the contralateral kidney. A high correlation was found between true volumes and areas on urography. The turnover time for urine in the hydronephrotic pelvis ranged from 47 to 473 min. The implications of this measurement for clearance values are discussed.