Effects of dutasteride and tamsulosin on penile morphology in a rodent model

ABSTRACT Purpose To evaluate the penile morphology after the isolated and combined administration of dutasteride and tamsulosin in a rodent model. Materials and Methods Forty male rats were assigned into the following groups: Control group (C, receiving distilled water, n=10); Dutasteride group (D, receiving 0.5 mg/Kg/day of dutasteride, n=10); Tamsulosin group (T, receiving 0.4 mg/Kg/day of tamsulosin, n=10); and Dutasteride associated with Tamsulosin group (DT, receiving both drugs n = 10). All drugs were administered via oral gavage. After 40 days, the animals were submitted to euthanasia and their penises were collected for histomorphometric analyses. Data were compared using one-way ANOVA followed by Bonferroni’s post-test, considering p<0.05 as significant. Results The sinusoidal space and smooth muscle fiber surface densities (Sv), and the cross-sectional penile areas of rats in groups D, T and DT were reduced in comparison to controls with the most notable reductions in the combined therapy group. The connective tissue and elastic system fibers Sv were augmented in groups D, T and DT in comparison with the control group, again with the most pronounced changes observed in animals receiving the combined therapy. Conclusion Both treatments with dutasteride or tamsulosin promoted penile morphometric modifications in a rodent model. The combination therapy resulted in more notable modifications. The results of this study may help to explain the erectile dysfunction observed in some men using these drugs.

摘要
目的：本研究旨在评估在啮齿动物模型中单独或联合应用度他雄胺（dutasteride）与坦索罗辛（tamsulosin）后的阴茎形态学变化。
材料与方法：将40只雄性大鼠随机分为以下四组：对照组（C组，给予蒸馏水，n=10）、度他雄胺组（D组，每日给予0.5 mg/kg度他雄胺，n=10）、坦索罗辛组（T组，每日给予0.4 mg/kg坦索罗辛，n=10）以及度他雄胺联合坦索罗辛组（DT组，同时给予两种药物，n=10）。所有药物均经灌胃给药。造模40天后，对所有大鼠实施安乐死，采集阴茎组织进行组织形态计量学分析。采用单因素方差分析（one-way ANOVA）结合Bonferroni事后检验对数据进行比较，以p<0.05为差异具有统计学意义。
结果：与对照组相比，D组、T组及DT组大鼠的阴茎血窦间隙、平滑肌纤维表面积密度（Sv）以及阴茎横截面积均显著降低，其中联合给药组的降低幅度最为显著。与对照组相比，D组、T组及DT组大鼠的结缔组织与弹性纤维表面积密度均显著升高，同样以联合给药组的变化最为明显。
结论：单独应用度他雄胺或坦索罗辛均可改变啮齿动物模型的阴茎形态计量学特征，联合给药的改变更为显著。本研究结果有助于解释部分服用此类药物的男性所出现的勃起功能障碍。