PDE_5基因特异性siRNA改善糖尿病性勃起功能障碍大鼠勃起功能的研究

The effect of Phosphodiesterase Type 5 siRNA on erectile function of rats with diabetic erectile dysfunction

目的探讨大鼠PDE_5基因siRNA对糖尿病性勃起功能障碍(DMED)大鼠PDE_5基因表达的抑制作用及其对DMED大鼠勃起功能的影响。方法构建可同时表达2条针对大鼠PDE_5基因的shRNA重组腺病毒; 50只雄性SD大鼠随机取10只作为正常对照。其余建立DM ED大鼠模型,随机分为实验组、阴性对照组和空白对照组,分别将重组腺病毒rAd-rPDE_5-shRNA、腺病毒rAd-mock及生理盐水注射于阴茎海绵体。注射后第7天,电刺激盆神经测定各组大鼠阴茎海绵体内压(ICP)及平均周围动脉压(MAP),然后取海绵体组织通过RT-PCR和Westem blot分别检测PDE_5基因mRNA及蛋白的表达。结果ICP/MAP实验组和正常对照组显著高于阴性对照组和空白对照组(P<0.05),实验组和正常对照组间无显著性差异(P>0.05);RT-PCR和Western blot分析,实验组大鼠PDE_5基因mRNA和蛋白表达均显著低于阴性对照组和空白对照组(P<0.05)。结论PDE_5基因shRNA重组腺病毒转染可以改善DMED大鼠的勃起功能,为DMED治疗方法的探索提供了新的思路。

Objective To investigate the effect of phosphodiesterase type 5 （PDEs） siRNA on inhibition of PDE5 expression and the erectile function of rats with diabetic erectile dysfunction（ED）. Methods Recombinant adenovirus rAd-rPDEs-shRNA containing two specific shRNA targeting PDE5 gene of rat was constructed. Fifty male SD rats were randomly divided into two groups including normal control group（10 rats） and model group with diabetic ED （40rats）. The model group then subdivided into 3 groups： experimental group, negative control group and blank control group respectively. Then rAd-rPDEs-shRNA, adenovirus rAd-mock and physiologic saline were injected into the corporal cavernosum of rats in corresponding group. On day 7 after injection, mean arterial pressure （MAP） and intracavernous pressure （ICP） induced by electrostimulation of penile dorsal nerves were measured in rats of each group. The expression of PDE5 in corporal tissues were detected gene by RT-PCR and Western blot respectively. Results The level of ICP/MAP in negative and blank control group was significantly lower than that in normal control group and experimental group （P〈0.05）, but no significant difference was found in level of ICP/ MAP between normal and experimental group （P〉0.05）. The level of PDE5 expression was significantly higher in experimental group than that in negative and blank control group （P〈0.05）. Conclusion These results suggested that in vivo rats penis transferred with PDE5 shRNA might improve erectile function in rat with diabetic ED, which provided a new therapeutic approach for treatment of diabetic ED.