淫羊藿苷对去势大鼠阴茎海绵体一氧化氮合酶亚型mRNA和蛋白表达的影响

Effect of Icariin on the mRNA and protein expression of NOS isoform in corpus cavernosum of castrated rats

目的 为探讨淫羊藿苷对勃起功能障碍(erectiledysfunction,ED)的长期疗效及其药理作用机制,观察长期口服淫羊藿苷对去势大鼠ED模型阴茎海绵体一氧化氮合成酶(NOS)3个亚型(nNOS、iNOS、eNOS)mRNA及蛋白表达的影响。方法 建立去势大鼠ED模型,随机分4组,分别连续灌服不同剂量淫羊藿苷和安慰剂3mon,采集静脉血测定血清游离睾酮,分离阴茎海绵体,利用RT-PCR和免疫组化分析方法,观察nNOS,iNOS和eNOS的mRNA和蛋白表达的变化。结果 去势后血清游离睾酮降低(P<0.01),灌服不同剂量淫羊藿苷对血清游离睾酮无明显影响(P>0.05)。去势大鼠阴茎海绵体nNOS、iNOS mRNA和蛋白表达较未去势组降低(P<0.01),eNOS则无表达,但是 灌服不同剂量淫羊藿苷3 mon后nNOS,iNOS的mRNA和蛋白表达较安慰剂增加(P<0.05)。结论 长期口服淫羊藿苷可提高阴茎海绵体NOS mRNA和蛋白表达,可能对勃起功能具有长期治疗效果。

ABSTRACT AIM To study the long-term efficacy of Icariin on erectile dysfunction (ED) and the pharmaceutical action mechanism, the effects of Icariin on the expression of mRNA and protein of NOS isoforms (nNOS, iNOS, eNOS) in corpus cavernosum(CC) of castrated rats ED after long-term oral administration were investigated. METHODS Twenty-four Wistar rats were randomly divided into 4 groups. ED animal model was constructed by surgically removes of testis and Icariin and normal saline was orally administrated for three months. Serum free testosterone was measured by ELISA analysis. The expression of mRNA and protein of NOS isoforms (nNOS, iNOS, eNOS) in CC of rats were detected by RT-PCR and immunohistochemical staining. RESULTS The level of serum free testosterone was decreased significantly in castrated rats ( P < 0. 01 ). Icariin has no significant influence on the level of serum free testosterone ( P > 0. 05 ). The expression of mRNA and protein of nNOS and iNOS in CC of castrated rats were decreased significantly (P <C 0.01), However, eNOS was not expressed. The expression of mRNA and protein of nNOS and iNOS in CC of castrated rats increased significantly after oral administration of icariin for three months compared with placebo, but no obvious influence on eNOS expression in CC. CONCLUSION With these results we suggested that Icariin can increase the mRNA and protein expression of nNOS and iNOS after long-term oral administration, which may indicate that Icariin has long-term therapeutic effect on ED.