The effect of chlorpromazine pretreatment on the vascular resistance in kidneys following warm ischaemia.

In studies of 45 rabbits pretreated by chlorpromazine, clamping of the renal artery was performed. Chlorpromazine 3.5 mg/kg was given intravenously 15 min before arterial clamping. The duration of the clamping period ranged from 0 to 180 min. After removal of the kidneys the influence of the pretreatment on the vascular resistance was examined in perfusion studies. Resistance patterns were measured during hypothermic perfusion. The results were compared with an identical group without pretreatment. The vascular resistance rose with the duration of clamping but was lower than in the control group. The maximal resistance attained after 60 min of clamping was approximately 50% lower. In another series of chlorpromazine pretreated animals clamping of the renal artery for 180 min was followed by reestablishment of the circulation for 24 and 48 hours. Perfusion studies were performed on kidneys after removal. The results were compared with a group without pretreatment. The vascular resistance was found to return to normal values more rapidly when the animals had been pretreated with chlorpromazine.