Department of Urology, Chonnam National University Medical School, Gwangju, Korea.
Urology. 2011 Jun;77(6):1381-6. doi: 10.1016/j.urology.2011.01.036. Epub 2011 Mar 31.
To investigate the effect of orchiectomy and androgen replacement on the expression of vascular endothelial growth factor (VEGF) in rat penile tissue.
Adult male Sprague-Dawley rats (12 weeks old) were left intact (control) or surgically castrated. Orchiectomized rats were left untreated or received testosterone propionate (TP) for 7 days, beginning 1 or 2 weeks after castration. Erectile function was assessed by measuring intracavernosal pressure in response to cavernous nerve stimulation, and the expression of VEGF protein and mRNA was determined by immunohistochemistry, Western blot analysis, and reverse transcriptase-polymerase chain reaction. Serum testosterone values were measured in each animal by radioimmunoassay.
Serum androgen levels decreased significantly in castrated animals, whereas TP injection normalized the serum levels of testosterone. Intracavernosal pressure was significantly decreased in untreated castrated rats (31.3 ± 15.7% at 2 weeks postcastration; 18.6 ± 4.6% at 3 weeks postcastration) compared with intact controls (58.0 ± 11.4% and 58.9 ± 8.2%, respectively). Erectile function was normalized in androgen-replaced rats, irrespective of treatment was initiation 1 or 2 weeks after orchiectomy. The expression of VEGF protein and mRNA was decreased in the corpus cavernosum of castrated animals compared with controls, whereas androgen replacement normalized the expression of VEGF. These results were consistently observed by all 3 methods of assessment.
These data suggest that androgen regulates the expression of VEGF in rat penile corpus cavernosum and confirms the importance of androgens in the maintenance of erectile function.
研究去势和雄激素替代对大鼠阴茎组织血管内皮生长因子（VEGF）表达的影响。
12 周龄雄性 Sprague-Dawley 大鼠保持完整（对照组）或手术去势。去势大鼠不治疗或在去势后 1 或 2 周开始接受丙酸睾酮（TP）治疗 7 天。通过测量海绵体神经刺激引起的海绵体内压来评估勃起功能，通过免疫组织化学、Western blot 分析和逆转录聚合酶链反应来确定 VEGF 蛋白和 mRNA 的表达。通过放射免疫法测量每个动物的血清睾酮值。
去势动物的血清雄激素水平显著下降，而 TP 注射使血清睾酮水平正常化。未治疗的去势大鼠的海绵体内压显著降低（去势后 2 周时为 31.3±15.7%；去势后 3 周时为 18.6±4.6%），与完整对照组相比（分别为 58.0±11.4%和 58.9±8.2%）。雄激素替代治疗可使去势大鼠的勃起功能正常化，无论治疗开始于去势后 1 周还是 2 周。与对照组相比，去势动物的海绵体组织中 VEGF 蛋白和 mRNA 的表达降低，而雄激素替代可使 VEGF 的表达正常化。这 3 种评估方法均观察到了相同的结果。
这些数据表明，雄激素调节大鼠阴茎海绵体组织中 VEGF 的表达，并证实了雄激素在维持勃起功能中的重要性。
