Kaya T, Sarioglu Y, Göksu O C, Yildirim S, Yildirim K
Cumhuriyet University, Faculty of Medicine, Department of Pharmacology, Sivas, Turkey.
Pharmacol Res. 1998 Mar;37(3):227-32. doi: 10.1006/phrs.1997.0285.
Recently, it has been demonstrated that the endothelium of corpus cavernosum (CC) plays an important role on smooth muscle relaxation, which is crucial to initiate and maintain erection. We investigated the effect of long-lasting additional testosterone propionate (TP) therapy on endothelium-dependent and -independent relaxations of isolated rabbit CC. Isolated CC strips were mounted in organ baths and isometric tension was recorded. Addition of a specific inhibitor of nitric oxide synthesis, NG-nitro-L-arginin methyl ester (L-NAME), into the organ bath had no effect on the relaxation responses to adenosine (ADO), adenosine 5'-triphosphate (ATP) and sodium nitroprusside (SNP) in isolated CC strips precontracted with phenylepherine, but completely inhibited relaxation responses produced by ADP. Adenosine and adenine nucleotides relaxed the phenylepherine-induced contractile response in control strips with the potency order: ADO (62.8 +/- 3.2%) > ATP (37.1 +/- 5.2%) > ADP (25.8 +/- 2.5%). The relaxation responses to ADO, ATP and SNP in isolated rabbit CC strips were not significantly altered by additional TP therapy. The relaxation responses produced by ADP were significantly enhanced following 1 and 2 months TP therapy as compared with controls. However, in the group treated with TP for 2 months followed by a 2 months drug-free period, relaxation responses were significantly reduced compared to 1 and 2 months treatment groups, and approached control values. Increased relaxation responses to ADP following 1 and 2 months additional TP therapy may be a result of increased endothelial purinergic receptor density, or it may be due to stimulation and/or release of endothelial nitric oxide (NO) by TP.
最近的研究表明，海绵体（CC）的内皮细胞在平滑肌舒张过程中发挥着重要作用，这对勃起的启动和维持至关重要。我们研究了长期额外使用丙酸睾酮（TP）治疗对离体兔海绵体内皮依赖性和非依赖性舒张的影响。将离体的海绵体条带安装在器官浴槽中，并记录等长张力。向器官浴槽中添加一氧化氮合成的特异性抑制剂Nω-硝基-L-精氨酸甲酯（L-NAME），对用去氧肾上腺素预收缩的离体海绵体条带对腺苷（ADO）、三磷酸腺苷（ATP）和硝普钠（SNP）的舒张反应没有影响，但完全抑制了ADP产生的舒张反应。腺苷和腺嘌呤核苷酸使对照条带中去氧肾上腺素诱导的收缩反应舒张，其效力顺序为：ADO（62.8±3.2%）>ATP（37.1±5.2%）>ADP（25.8±2.5%）。额外的TP治疗并未显著改变离体兔海绵体条带对ADO、ATP和SNP的舒张反应。与对照组相比，TP治疗1个月和2个月后，ADP产生的舒张反应显著增强。然而，在TP治疗2个月后再经过2个月无药期的组中，与1个月和2个月治疗组相比，舒张反应显著降低，并接近对照值。额外TP治疗1个月和2个月后对ADP舒张反应的增加可能是内皮嘌呤能受体密度增加的结果，也可能是由于TP刺激和/或释放内皮一氧化氮（NO）所致。
