腎阻血の腎皮質糖新生能に及ぼす影響

抄録

This study was designed to determine changes in one of metabolic functions, gluconeog-enesis after ischemic renal injury. Right kidneys of SD rats were removed and a vascular clamp was placed across the left renal artery and vein for 0, 10, 30, 60 and 90 min. On 1, 3 and 7 days after the treatment, tubule suspensions were prepared by collagenase treatment of left kidneys and incubated with or without 2mM pyruvate or malate aerobically. After the incubation, glucose contents were assayed photometrically. Serum creatinine was also determined. In addition, morphological changes were observed under light microscopy to examine the relationship between metabolism and morphology. The tendency of increase of gluconeogenesis was observed on day 1 and 3 after 10, 30, 60 min of ischemic time. On the other hand, gluco-neogenesis decreased significantly on day 1 after 90 min treatment. In contrast, on day 1 and 3 after treatment, serum creatinine levels showed no difference from control at the groups of 10 and 30 min ischemia. Whereas it rose significantly at the group of 60 min ischemia, showing a different tendency from that of the increase of gluconeogenesis. Moreover, morphologic damage was observed on day 1 and 3 after ischemia of 30 and 60 min. The morphologic damage was found more advanced in the corticomedullary region than those of the cortex which has the high gluconeogenic activity and which thus showed relativly limited damage. These results suggest that renal gluconeogenesis is relatively insusceptible to ischemic injury. The fact that it increased up to 60 min of ischemia could be conceived as the reactions by acidosis, compensation for tissue damage, supplement energy for ATP decrease and for further regeneration as emergency responses and the actions for maintaining the blood glucose level.