Experimental partial ureteric obstruction in newborn rats. IV. Do the morphological effects progress continuously?
Partial obstruction of the ureter was created in newborn rats, and its effects were studied after 1, 2, 3, 6 and 9 weeks--that is, until adult age. Within 1 week, a considerable hydronephrosis had appeared. Within 2 weeks, parenchymal weight was found slightly reduced (8 per cent) on the obstructed side, and, within 3 weeks, equivalently increased on the contralateral, intact side. After these points in time, there was no further deterioration. Histological examination revealed marked deformation of the papilla and minor foci of degeneration and inflammation within 1 to 2 weeks which tended to become chronic in type after 3 to 9 weeks. Arterial hypertension was not noted. Thus, the effects of partial ureteric obstruction on the renal parenchyma are 1) discrete, 2) not in proportion to the degree of hydronephrosis, 3) fully compensated by contralateral hypertrophy and 4), after reaching an early maximum, not increasing with time.
D000375:Aging; D000818:Animals; D000831:Animals, Newborn; D006869:Hydronephrosis / Q000209:etiology; D006984:Hypertrophy; D007668:Kidney / Q000473:pathology*; D009929:Organ Size; D051381:Rats; D011919:Rats, Inbred Strains; D013997:Time Factors; D014517:Ureteral Obstruction / Q000473:pathology* / Q000503:physiopathology