[Study of gamma-GTP activity in urine and renal tissue of experimental warm ischemic kidney].

The acute changes of proximal tubule function and its pathological condition were investigated by measuring (gamma-GTP) activities in the urine and renal tissue using warm ischemic kidneys of adult dogs (n = 34). Eight kidneys were kept in a warm ischemic condition throughout the experimental period and the tissue was extirpated from the kidney at every hour, and 31 kidneys were released from the 30 min ischemic condition. The urine and the blood (peripheral and renal artery and vein) were collected from these kidneys at every hour up to 5 hr. The kidneys observed for urine outflow (n = 24) were divided into three groups with time; 7 kidneys (1 hr), 5 kidneys (3 hr), and 12 kidneys (5 hr), and they were extracted. The gamma-GTP activity of the urine showed the maximum value of 851 +/- 102 mIU/ml at 30 min and decreased to 217 +/- 56 mIU/ml, which declined to be close to the starting value of 133 +/- 26 mIU/ml, at 5 hr after the warm ischemic condition was released. The gamma-GTP activities of the cortex were 325 +/- 62 mIU/mg.p (1 hr), 527 +/- 37 mIU/mg.p (3 hr), and 266 +/- 44 mIU/mg.p (5 hr). However, no increase in gamma-GTP activity was observed either in the renal vein blood, or in the cortex obtained from the 8 kidneys kept in the warm ischemic condition. A histopathological examination showed the progressive changes in some parts of the proximal tubules after release from the ischemic condition.(ABSTRACT TRUNCATED AT 250 WORDS)