RESUMO
Objective To investigate the expression and activity of transforming growth factor-β1 (TGF-β1)and endothelial nitric oxide synthase(eNOS) in the cavernous vascular structural remodeling of diabetic rats.Methods 52 adult male SD rats were randomly assigned to experimental group(DM) and control group(NDM).In DM group,diabetes was induced in rats 4 days after intraperitoneal injection with streptozotocin.HbA1c was measured on 2,4,8,and 16 weeks after injection.Penile tissues were harvested.The protein expression of TGFβ1 and eNOS in situ was evaluated by the Envision immunohistochemistry.Results Compared to NDM group,the expression of the HbA1c increased significantly in DM group on the 16th week(P ＜0.01),both the penile erection rate and penile erectile times decreased significantly in DM group on the 16th week (P ＜ 0.01),and the value of eNOS decreased on the 16th week(P ＜0.01).The expression of TGF-β1 went up in DM group compared to NDM group on the 8th week (P ＜ 0.01) and sustained to the 16th week (P ＞ 0.05).In DM group,we found that TGF-β1 protein in cavernous body of penis was positively related with age in weeks(r =0.947,P ＜0.01) ; and eNOS in cavernous body of penis was negatively related with age in weeks (r =-0.945,P ＜ 0.01).Meanwhile,the expression of TGF-β was negatively related with the eNOS(r =-0.891,P ＜0.01).Conclusion Our results indicate that TGF-β1 plays an important role in the pathogenesis of diabetic erectile dysfunction(ED) and TGF-β1 inhibition may be a promising strategy to prevent development of diabetic ED.