POSTISCHEMIC RECOVERY PROCESS OF RENAL OXYGEN-CONSUMPTION IN NORMAL AND STREPTOZOTOCIN-DIABETIC RATS

We tried to study in depth the recovery process in the cortical and th e medullary oxygen (02) consumption of normal and streptozotocin diabe tic rat kidneys after ischemia. It was found that the cortical and the medullary 02 consumption decreased after ischemia, reaching their low est levels at 1 day after every ischemic duration in normal and diabet ic kidneys. In the period prior to ischemia to 1 day after ischemia, n o significant difference was seen in the decrease in O2 consumption be tween the cortex and the medulla in normal kidney, whereas the medulla ry 02 consumption significantly decreased compared with the cortical 0 2 consumption in diabetic kidney. From 1 day to 4 weeks after ischemia , the increase in the cortical 02 consumption was significantly higher than that in the medulla of normal kidney. In contrast, the increase in the medullary 02 consumption was significantly higher than that in the cortex of diabetic kidney. Consequently, up to 4 weeks after ische mia, the decrease in the cortical 02 consumption was significantly low er than in the medulla of normal kidney, while there was no significan t difference regarding the decrease in 02 consumption between the cort ex and the medulla in diabetic kidney. These results suggest that ther e is a clear difference in the postischemic recovery process Of 02 con sumption between the cortex and the medulla, and also between normal a nd diabetic rat kidneys.