2-KIDNEY, 2 CLIP RENOVASCULAR HYPERTENSIVE RATS CAN BE USED AS STROKE-PRONE RATS

Background and Purpose-The cerebrovascular lesions in stroke-prone spo ntaneously hypertensive rats are not only dependent on high blood pres sure but partly related to pressure-independent genetic factors. The a im of the present study was to observe whether spontaneous stroke occu rred in renovascular hypertensive rats without a genetic deficiency. M ethods-The 1-kidney, 1 clip (1k1c); 2-kidney, 1 clip (2k1c); and 2-kid ney, 2 clip (2k2c) methods were used to induce hypertension in male Sp rague-Dawley rats with a ring-shaped silver clip. Sham-operated rats w ere used as controls. Blood pressure and neurological symptoms were ob served in the rats without any artificial inducement. Brain sections s tained with hematoxylin-eosin and phosphotungstic acid-hematoxylin wer e examined under a microscope to determine stroke foci. Results-The at tack rate of stable hypertension was 100% (55/55) in the 2k2c group, w hich was significantly higher than that in the 1k1c (23/30, 76.7%) and 2k1c (21/30, 70%) groups (P<0.01). None of the rats in the 2k2c group died of acute renal failure or suffered from diffuse cerebral lesions postoperatively, Forty weeks after renal artery constriction, the inc idence of spontaneous stroke in the 2k2c group was 61.8% (34/55), whic h was significant higher than that in the 1k1c (7/30, 23.3%) and 2k1c (5/30,16.7%) groups (P<0.01). Stroke foci were not observed in normote nsive controls. Conclusions-We conclude that 2k2e renovascular hyperte nsive rats with proper renal artery constriction can be used as stroke -prone renovascular hypertensive rats independent of a genetic deficie ncy.