The Study Of Leptin And Vascular Endothelial Fucntion In Diet Induced Obese Rats

ObjectiveThrough diet-induced obese rat (DIO) modeling, to observe the changes of biochemical indicators such as Leptin and so on, and also observe hemodynamic effects in rats.To study the relationship of the changes of blood Pressure and endothelial function.To exPlore the mechanism between Leptin and blood Pressure in obesity rats.Methods1.40male SD rats were divided into control grouP (grouP A) and obesity grouP (grouP B、C and D), grouP A was fed with normal diet, the others were fed with high-fat diet, the changes in body weight and body length which were used to determine obesity model.2.Serological tests:Blood was drawn from the angular vein of rats that were not fed overnight at the end of10、12and14week respectively. Serum levels of total cholesterol (TC),triglyceride(TG),fasting glucose (GLU) and high-density cholesterol (HDL-C) were detected.The serum levels of nitric oxide(NO),nitric oxide synthase(NOS) suPeroxide dismutase(SOD), SuPeroxide anion,and Leptin was also measured simultaneously.4.Blood Pressure test:after the anesthesia,the rats were infused with acetyleholine and sodium nitroPrusside respectively for5minutes thlough the left jugular vein catheter,at the rate of50g/kg min. Systolic Pressure was recorded through a carotid artery catheter simultaneously.Results1.comPared with the control grouP, there was a significant increase in body weight after10weeks of high fat feeding(P<0.01), and also significantly increased in Lee’s index(P<0.05);2with the increasing weight of diet-induced obese (DIO) rats, serum Leptin levels were markedly increased than in control grouP (P<0.01); comPared with the control grouP, serum levels of NO、 eNOS and SOD were lower (P<0.05), TNOS and iNOS were higher (P<0.05), SuPeroxide anion was no significance(P<0.05);4. Significant difference between control grouP and obesity grouP was shown in basic systolic blood Pressure (P<0.05), the decreasing magnitude of systolic blood Pressure was markedly lower than the control grouP by the way of intravenous injection of acetylcholine and sodium nitroPrusside,(P<0.01), the decreasing magnitude of systolic blood Pressure was markedly higher caused by sodium nitroPrusside than acetylcholine in each obesity grouP (P<0.05), there was no difference in between injection of acetylcholine and sodium nitroPrusside in control grouP(P>0.05).