Apoptosis of Pancreatic Beta Cells in Pregnant Insulin-resistant Rats Fed with High-fat Diet

摘要

cqvip:Objective The aim of this study is by observing the number change of islets beta cells in gestational rats exposed to high fat diet, tofurther reveal the mechanism of gestational diabetes mellitus. Methods Female Wistar rats were exposed to high fat diet for five weeks, and then became pregnant. During pregnancy dynamically detected indicators of glucose and fat. Until the third trimester of pregnancy evaluated the sensitivity of insulin and glucose tolerance. After executed rats, selected pancreatic tail tissue and fixed, further slides were stained with insulin antibody by immunohistochemistry to confirm the location of beta cells. Image analysis system determined mean area stained positive cells in each islet, which stood for total number of beta cells. The apoptotic beta cells in islet were detected and quantified by the Tunel technology to calculate apoptosis ratio. Results The level of free fatty acids in rats exposed to high fat diet was significantly higher than the control groups, and insulin resistance was more serious. Compared mean stained positive area among each group, the largest was gestational rats fed high fat diet, and gestational rats was larger than virgin rats, but the difference had no statistical significance. About apoptoticratio of beta cells was higher in diet intervened rats, gestational rats were higher than virgin rats. The same trend happened in the number of positive cells, but discrepancy was not remarkable. Conclusion Based on insulin resistance, apoptosis of pancreatic beta cellsincreased in gestational ratstaking high fat diet, through changing the number of beta cells to down regulate the pancreas endocrine function. That may be the mechanism of gestational mellitus.