抄録
The influence of temporary renal ischemia upon renal tubular function was experimentally investigated with stop flow technique which had been first described by Malvin et al. in 1957. The experiments were performed on five groups of mongrel dogs weighing 12 to 38kg. In Group 1, which was served as a control group, renal tubular transport patterns of Na, Cl, K, H+, PAH and water were studied with stop flow technique and in the same time glomerular filtration rate and renal plasma flow were determined on the both sides. The patterns and values of each side were compared. In Groups 2, 3 and 4 clamps were applied on the right renal pedicle for 30, 60 and 120 minutes, respectively. Stop flow patterns and renal clearance values were examined bilaterally 7 days and 14 days after release of the clamping. Afterwards, the kidneys were removed and examined microscopically.
The obtained results were as follows:
1) In Group 1 there was no significant difference of renal tubular transport patterns on the both sides.
2) In Group 2 renal tubular transport patterns of Na, Cl, K, H+, PAH and water, and clearance values such as GFR and RPF restored to the normal within 7 days after the clamping.
3) In Group 3 GFR and RPF restored to the normal within 7 days after the clamping, while renal tubular transport patterns on the 7th day following the clamping revealed some changes: decreases of Na, Cl and water reabsorptions and H+ secretion in the distal portion of the tubuli, a decrease of PAH secretion in the proximal portion of the tubuli and increased excretion of K. But, these changes were already disappeared in the stop flow patterns 14 days after the clamping.
4) In Group 4 even after 14 days some disturbances of renal clearance values were observed and renal tubular transport patterns on the 14th day following the clamping showed the same changes which were found in the stop flow patterns of Group 3 seven days after the clampig.
5) Following the clamping various stages of ischemia of the glomerular tufts and degeneration of the tubular epitheliums were observed according to the grades of ischemia in the microstudy of the kidneys. In the second week after the clamping, where functional restoration began to take place, the chief changes were flattening of the epitheliums and dilatation of the tubular lumens.
