| Objective:To establish the model of type2diabetic peripheral neuropathy in rats, with approximate human patients insulin resistance characteristics and pathological processes, and provide a reliable experimental evidence for clinical researching of the mechanism of diabetic peripheral neuropathy.Methods:Male Spragul-Dawley rats of clean grade160were randomly divided into120experimental group and a control group of40, the control group with normal diet, the experimental group was fed with high fat high sugar diet for4weeks. Then the experimental group intraperitoneal injection of1%STZ for the first time according to the dose of25mg/kg weight, the control group were injected0.1mmol/L volume of citrate buffer solution. Determination of blood glucose level24hours after the injection. After4weeks, give the experimental group intraperitoneal injection of1%STZ for the second time according to the dose of40mg/kg weight,the random blood glucose≥13.8mmol/L were to become the diabetic model.Then after12weeks,most rats become to the model of type2diabetic peripheral neuropathy. Detected body weight and blood glucose in different stages of rats. Collect the peripheral blood, Abbott automatic biochemical analyzer blood glucose,lipids,glycosylated hemoglobin, Roche electrochemical luminescence was measured insulin and calculate insulin sensitivity index. In the model rats after eight weeks,take them to EMG examination, determination of rat sciatic nerve conduction velocity. Take sciatic nerve transmission electron microscope to observe whether injury occurs. Based on the above indexes to judge whether the experimental rats were diabetic peripheral neuropathy.Results:1. Determination of experimental rats blood lipid and glycated hemoglobin levels:TG wasl.80±0.30; TC wasl.53±0.18; LDL was0.78±0.07;HDL was0.86±0.05, compared with the control group was statistically significant (P <0.01);the level of glycated hemoglobin was6.67±0.28, compared with the control group was statistically significant (P<0.01).2. Determination of insulin in experiment rats:the insulin levels was39.51±1.60, compared with the control group was statistically significant (P<0.01); insulin resistant index was42.92±4.35,compared with the control group was statistically significant (P<0.05)3. The experimental rats EMG physiological indicators:sciatic Nerve conduction latency1.47±0.10,compared with the control group was statistically significant (P <0.01)。Conclusions:1. High fat high sugar diet fed combined with STZ injection can successfully replicate the experimental type2diabetic rat model which have similar process and insulin resistance characteristics with the human diabetes.2. The model with hyperglycemia, hyperlipidemia, hyperinsulinemia and insulin resistance and other characteristics can cause peripheral neuropathy, it is an ideal animal model for study of diabetic peripheral neuropathy mechanism3. The model of good stability after the mold, conducive to subsequent drug intervention study. Objective:To check the expression level oxide enzyme (SOD, CAT, GPX), AR in DPN rats sciatic nerve in different period (before and after using Epalrestat intervention), combined with the change of rats sciatic pathological tissue morphology, peripheral neuropathy DPN rats antioxidant enzymes and the relationship between the AR and antioxidant enzymes and the change of the one after treatment.Methods:the first part we established46diabetic neuropathy in rats model, the rats will be divided into four groups:the nDM (ARI-); The nDM (ARI+); DPN (ARI-); DPN (ARI+), give the ARI100mg/kg/d per day, six weeks intervention treatment, then the22th week we put to death in the rat and using Western blot method respectively in each rat sciatic nerve tissue SOD, CAT, GPX, AR expression, using immunohistochemical method to detect the expression of rat sciatic nerve tissue of the above material and positioning, application of projection electron microscope observation of sciatic pathological changes tissue morphology. Comprehensive analysis of DPN rats peripheral neuropathy and antioxidant enzymes and the relationship between the AR and ARI antioxidant enzymes and the change of the AR after treatment.Results:1the electron microscope results showed sciatic nerve fibers twisted variant, highly oedema thickening, plate layer structure, disordered arrangement loose, plate layer separation and shrivel, board layer to the lateral axon form protrusions. Schwann cell structure, vacuoles degeneration, cell membrane is still intact. No myelinated nerve fiber cell swelling and shrinking form irregular, visible cavity structure, widened gap. Schwann cells are shrinking. Given in accordance with the company he has improved after lavage2Western blot results show that with the progress of the course of the disease, the expression of SOD in the experimental group and control group, experimental group and control group of GPX expressed as; Experimental group and control group expressed as CAT, are characterized by progression gradually decline, after feeding the medicine is increasing. Experiments for each AR expression, control group for AR expression, gradually increased along with the progression and decreases gradually after feeding. Antioxidant enzymes and AR expression in different blood glucose levels in the same course of the group has no statistically significant difference.3immunohistochemical results show SOD, CAT, GPX positive signal is mainly expressed in cytoplasm and cell membrane, particularly the schwann cell nucleus, schwann cytoplasm, myelin sheath. AR expression mainly in sciatic nerve schwann cells, expression of myelin sheath and axon in there is very little.Conclusion:1diabetes rat sciatic nerve tissue damage degree is closely related to the course of the disease.2diabetes, the expression of antioxidant enzymes SOD, GPX and CAT with the course of the disease gradually reduced, leading to enhanced oxidative stress.3polyol pathway activation may be one of the important mechanisms of diabetic sciatic nerve tissue pathological changes, the expression of AR enhancement was correlated with oxidative stress.4diabetes rat peripheral nerve tissue pathological changes is closely associated with oxidative stress... |
PDF Full Text Request