Acceleration of Hypertension and Development of Stroke in the Spontaneously Hypertensive Rat by Unilateral Ureteral Obstruction

Abstract

Unilateral ureteral obstruction (UUO) in 6-week old male spontaneously hypertensive rats (6-w-SHR) accelerated the elevation of blood pressure and developed stroke with high frequency from 3 weeks after operation, whereas UUO had no effect in either 20-week old SHR or 6-week old normotensive Wistar Kyoto rats. Urinary protein excretion and plasma urea and renin concentrations in 6-w-SHR began to increase 2 weeks after UUO. Removal of the obstructed kidney in 6-w-SHR one week after UUO prevented the acceleration of hypertension, while the same treatment 2 weeks after operation did not. In the ureter-obstructed kidneys of 6-w-SHR, hydronephrotic atrophy was markedly observed already one week after operation, while in the opposite kidneys, hypertensive vascular lesions were manifested from the second week. These results indicate that with regard to reversibility of the hyperhensive process, the obstructed kidney is more important in the early postoperative stages and the contralateral kidney more important later.