The Role Of Oxidative Stress In Rats With Experimental Type 2 Diabetes And Its Brain Lesions

Objective:To investigate the changes of AR,O₂^-·,SOD,CAT activity in diabetic microangiopathy and nervous tissue.O₂^-·is a oxidative stress product,SOD and CAT are oxidizing material catabolic enzymes.To interpret exceptional biochemistry change antioxidation in cerebral vessels microenvironment.identify the relation between the changes of AR activity and hyperglycosemia,oxidative stress.Methods:Healthy adult male 120 SD rats were randomly divided into normal control group and diabetic group.The diabetic group feed with high glucose and high fat bait vessel,Diabetic rats were induced by injection of streptozotocin(STZ) intraperitoneally.The ones whose blood glucose is above 13.8 is succeed.Select 15 SD rats(blood glucose:13.8～16.7)is diabetes group Low.Select 15 SD rats(blood glucose＞16.7)is diabetes group High.Then take blood and brain tissue of there groups respectively.Make pathological section to observe alteration.The activity of AR in the blood and brain tissue were measured by NADPH decreasing test method. The activity of SOD and CAT were measured by bioehemieal test method in eaeh group of the experiment.Results:①pathological section:normal control group:not fingd obviously histopathological change.diabetes group Low and High:micrangium basal lamina thickening,endotheliocyte swelling,hyperplasia,hyalinosis,lumens narrow,tubal wall to sink,support loss,gliocyte swelling,nucelus vanish,endochylema muddy, astrocyte cloudy swelling.②Diabetic SD rat group L the activity of O₂^-·(95.87±24.58)is higher than control group(65.94±11.38)significantly(P＜0.05),Diabetic SD rat groupH the activity of O₂^-·(105.43±22.86)is higher than control group significantly(P＜0.01),the difference with the diabetic SD rat group L did not achieve statistical significence(P＜0.05).③Diabetic SD rat group L the activity of SOD(23.65±7.62)is lower than control group(8.93±12.01)significantly(P＜0.05),Diabetic SD rat group H the activity of SOD(16.41±6.82)is lower than control group significantly(P＜0.05),the difference with the diabetic SD rat group L achieve statistical significence.(P＜0.05)④Diabetic SD rat group Low the activity of serum AR(208.95±11.04)is higher than control group(257.63±11.55)significantly(P＜0.05),Diabetic SD rat group High the activity of AR(201.96±11.05)is hinger than control group significantly(P＜0.05), the difference with the diabetic SD rat group L achieve statistical significence. (P＜0.05)Diabetic SD rat group L the activity of brain tissue AR(4.16±0.96)is higher than control group(2.44±1.27)significantly(P＜0.05),Diabetic SD rat group H the activity of AR(4.44±1.05)is higher than control group significantly(P＜0.05),the difference with the diabetic SD rat group L achieve statistical significence.(P＜0.05)There is no significant difference in AR activity beteen serum and brain tissue.The rate of increase of AR activity in brain tissue is higher than in serum.⑤the difference of serum CAT activity in every group did not achieve statistical significence(P＞0.05)Conclusion①pathological section:normal control group:not fingd obviously histopathological change,diabetes group Low and High:fingd obviously histopathological change.Indicate micrangium nerve tissue pathological changes.②the activity of O₂^-·in diabetes group Low and High is higher than normal control group,the diabetes group High is more significant,indicate when in diabetic microangiopathy and nervous tissue,oxidative stress strengthen,but the activity do not change with blood glucose concentration.③the activity of SOD in diabetes group Low and High is lower than normal control group,indicate when diabetic microangiopathy and nervous tissue,hyperglycosemia is main reason of ROS priming,the activity of SOD is different significantly between diabetes group low and high,the SOD activity was associated with blood glucose concentration.④the activity of AR in diabetes group is higher than control significantly,but this difference can not be observed between the diabetic group Low and diabetes group High.indecate when diabetic microangiopathy and nervous tissue,AR change with oxadation and oxadation resisting system,diabetic microangiopathy and nervous tissue damage is correlated close with O₂^-·,SOD,AR,SOD is most significantly, it is maybe the key reason in disbalance resulting complication occurred.the difference between the diabetic group Low and diabetes group High indicate AR activity do not change with blood glucose concentration.The rate of increase of AR activity in brain tissue is higher than in serum,indicate AR is correlated close with diabetic microangiopathy and nervous tissue damage.⑤the difference of serum CAT activity in every group did not achieve statistical significence,maybe there is lab error.