[Influence of sucrose administration on blood insulin level, and number of insulin receptor and affinity on isolated hepatocytes].

In order to investigate the process to form diabetic-like condition by giving continuously excessive amount of sucrose, rats were maintained with purified water (Purified Water Group, PWG) and 10% sucrose solution (Sucrose Group, SG), as drinking solution, ad libitum for 5 months, and were subjected to the following experiments: 1) Serum glucose (BG) and insulin level (IRI) in sucrose tolerance test (STT) were measured periodically up to 24 hours after administration. 2) The number and affinity of insulin receptor on isolated hepatocytes from the rats of PWG and SG were also investigated. At the termination of the experiment, 5 months after the initiation, the BG and IRI levels in SG were significantly higher compared to those of PWG. In STT, SG showed reduced glucose tolerance and also high blood insulin level. The number of insulin receptor of isolated hepatocytes of SG was approximately 23% lower than that of PWG and the affinity of SG was slightly lower than that of PWG. These results suggest that continuous high BG and IRI levels are indicated in the rats given large amount of sucrose continuously. The number of insulin receptor of such rat was also reduced by down regulation, resulting in an insulin-resistance. These cause further high blood glucose level and abnormality in metabolism, to result in a prediabetic impaired glucose tolerance.