The uptake of hippuran in kidney slices employed as a viability test

The 125I-Hippuran renogram in rabbit kidneys after graded warm ischaemia

125I-Hippuran renography was performed after temporary renal arterial clamping in contralateral nephrectomized rabbits. Mean renograms for the experimenttal groups were calculated for 0, 1, 1 1/2, 2, 2 1/2 and 3 h of warm ischaemia. The appearance phase, the 1 min uptake phase and excretion ratio were evaluated. The kidney function was monitored by serum-creatinine. Warm ischaemia of 1, 1 1/2 and 2 h resulted in a late maximum peak and delayed excretion, and for the last group in an accumulation curve. The uptake capacity was normal for these groups. Protracted ischaemia of 2 1/2 and 3 h affected also the appearance and uptake phase resulting in a slower and decreased Hippuran uptake of 50% and 34% respectively. Duration of warm ischaemia and changes in the renogram were well correlated. A normal uptake phase predicts restitution of the kidney function and 100% survival.

The effect of chlorpromazine pretreatment on the vascular function of kidneys damaged by warm ischaemia and cold storage in Collins' solution

Vascular resistance was determined in 40 rabbit kidneys after graded warm ischaemia up to 60 minutes and preservation in Collins' solution for 24 and 48 hours. Half of the animals were treated with chlorpromazine 3.5 mg/kg before induction of the ischaemia. Vascular function was determined during short-term perfusion with TIS-U-SOL at 4 degrees C. The experiments showed that warm ischaemia of 30 and 60 minutes duration gave an increase in vascular resistance. The increase was, however, smaller in kidneys pretreated with chlorpromazine. Preservation in Collins' solution for 24 and 48 hours did not change this correlation. Determination of the weights and thereby formation of oedema showed that all kidneys preserved had a small increase in weight. No difference was found between pretreated kidneys and untreated kidneys. It is concluded that pretreatment with chlorpromazine is capable of diminishing vascular contraction during the warm ischaemic period and that preservation in Collins' solution for up to 48 hours does not alter this beneficial effect.

The effect of chlorpromazine pretreatment on tubular function in kidney preservation

The effect of Chlorpromazine pretreatment on tubular function was investigated. Hippuran uptake in cortex slices from rabbit kidneys was measured after one hour of incubation in a medium containing Hippuran. Before measurement the kidneys were exposed to varying periods of warm ischaemia or/and cooled and preserved for 24 hours in Collins solution. Chlorpromazine treated and untreated groups of animals were compared, the results obtained were identical in both groups. In contra distinction to these findings, addition of Chlorpromazine to the incubation fluid inhibited uptake of Hippuran in the kidney slices. The effects of pretreatment with Chlorpromazine on the kidney function after ischaemic damage were demonstrated. Serum-creatinine and survival were compared in a treated and an untreated group after 3 hours of temporary clamping of the renal artery. Pretreatment resulted in earlier onset of function and better survival. It is concluded that the antimetabolic effect of Chlorpromazine is opposed to its vasodilatory properties is of little practical importance for the viability of the kidney damaged by ischaemia.