Yang Rong, Huang Yun-Ching, Lin Guiting, Wang Guifang, Hung Steven, Dai Yu-Tian, Sun Ze-Yu, Lue Tom F, Lin Ching-Shwun
Knuppe Molecular Urology Laboratory, Department of Urology, School of Medicine, University of California, 533 Parnassus Ave., Box 0738, San Francisco, CA 94143-0738, USA.
Biochem Biophys Res Commun. 2009 Mar 20;380(4):758-62. doi: 10.1016/j.bbrc.2009.01.144. Epub 2009 Jan 29.
It has been reported that penile PDE5 expression was under androgen regulation. However it remained unknown whether the observed change in PDE5 expression in castrated animals was under direct androgen regulation or due to changes in smooth muscle content. In the present study we showed that castration of rats caused a reduction of penile size and cavernous smooth muscle content. Immunostaining detected concomitant reduction of PDE5 and alpha smooth muscle actin (alpha-SMA) expression in the corpus cavernosum of castrated rats. Real-time PCR and Western blotting detected no change of PDE5 expression when normalized with alpha-SMA expression in castrated rats. Androgen receptor (AR) expression was increased while PDE5 expression remained unchanged in DHT-treated rat cavernous smooth muscle cells (CSMC). Prostate specific antigen (PSA) promoter activity was upregulated while PDE5A promoter activity remained unchanged in DHT-treated CSMC. Thus, PDE5 expression was not under direct androgen regulation.
据报道，阴茎磷酸二酯酶5（PDE5）的表达受雄激素调控。然而，去势动物中观察到的PDE5表达变化是受雄激素直接调控还是由于平滑肌含量的变化，仍不清楚。在本研究中，我们发现大鼠去势导致阴茎尺寸和海绵体平滑肌含量减少。免疫染色检测到去势大鼠海绵体中PDE5和α平滑肌肌动蛋白（α-SMA）表达同时减少。实时定量聚合酶链反应（PCR）和蛋白质免疫印迹法检测发现，去势大鼠中以α-SMA表达进行标准化时，PDE5表达无变化。在双氢睾酮（DHT）处理的大鼠海绵体平滑肌细胞（CSMC）中，雄激素受体（AR）表达增加而PDE5表达保持不变。在DHT处理的CSMC中，前列腺特异性抗原（PSA）启动子活性上调而PDE5A启动子活性保持不变。因此，PDE5表达不受雄激素直接调控。
