| Objective:We used the model of diabetes rats with erectile dysfunction (ED) to investigate the molecular mechanisms of ED and the relation between oxidative stress injury and ED。We also want to improve the model of streptozotocin-induced diabetes rats with ED, and to detect the expression of GSH、GSH-Px、Bax and Bcl-2in rats corpus cavernous tissue we also observed the microstructure and ultrastructure change of the rats corpus cavernosum tissue and the smooth muscle tissue.Methods:Grouping and modeling:sixty ten week old male sprague-dawley(SD) rats were selected.weighing (247±26g).They were randomly divided into three groups: nomal control group, buffer control group, diabetes group. By the method of tail vein injection of STZ (60mg/kg). we could succesfully establish the rat model of diabetes. After96hours, once the random blood glucose of rats is greater than16.7mmol/L. we can identify the diabetes model success. Eight weeks later. We would subcutaneously inject APO to observe penile erection, eretion incubation period(from the administration of APO to the time of erection) and eretile positive rate in30minutes.Specimen collection and Laboratory testing:microscopy and electron microscopy would be used to observe the vascular endothelial tissue morphological changes of penis. We also use the colorimetric and immnohistochemistry for quantitative and qualitative detection of GSH.GSH-Px, Bax and Bcl-2in the corpus cavernosum tissue of rats.The statistical analysis:data among each experimental group were expressed as mean=standard deviation.T-test or multi-factor analysis of variance were used between groups. P value less than0.05was considered statistially significant.Results:19of20STZ rats were successfully modeled, which account for95%. All the rat with diabetes appear the diabetes symptoms.like polydipsia. polyphagia. polyuria and apparent weight loss. Four rats died of infection or ketoacidosis, so the fatality rate is 21%. The number of penile erection and erectile positive rate between the control group and the DM group were significantly different. We use APO to identify erectile dysfunction in the DM rats. Compared with the control group, the GSH and GSH-Px were significantly decreased in the DM erectile dysfunction group. Immunohistochemical staining showed that Bax and Bcl-2are mainly expressed in the cytoplasm of vascular endothelial cells of penis,mostly brown, dark brown coloring-based. Compared with the control group, the ratio of Bcl-2/Bax is significantly lower(P<0.05). Under the light microscope, we can find that the corpus cavermnosum muscle cells were shinking,the number were reduced and increasing fibrosis of endothelial cells. Under the electron microscope, multiple fracture of sinusoidal endothelial cells and small vascular endothelial cell proliferation were seen. in addition.the endothelial cell membrane attachment of many small medullary structure blocked the lumen. We can observe the phenomenon of nuclear deformity, separation of the chromatin. small vessels basment membrane thicken, increased vacuole in vessel wall and the junction gaps between endothelial cell were widened.Conclusions:In our study, we used the animal model of diabetes rats with erectile dysfunction to look for markers of oxidatives stress. SD rats were successfully used to study DM ED model. Spectrophotometric and immunohistochemical staining and electron microscopy were applied to study the change of antioxidant substances and cell ultrastructure in the corpus tissue of rats. Our study shows that the content of GSH and GSH-Px deseased. Bcl-2and Bax regulate the apoptosis of penis. In DM ED rats, the ratio of Bcl-2/Bax is lower than the control group.We find that the fibrosis of endothelial cell and the damage of mitochondria. This may demonstrate that DM erectile function may related to oxidative stress injury. We can speculate that long term application of antioxidants may enhance the antioxidant ability, which may helps to treat DM erectile dysfunction. |
PDF Full Text Request