Nagai Atsushi, Hara Ryoei, Yokoyama Teruhiko, Jo Yoshimasa, Fujii Tomohiro, Miyaji Yoshiyuki
Department of Urology, Kawasaki Medical School, Kurashiki, Okayama, Japan.
Int J Urol. 2008 Oct;15(10):915-918. doi: 10.1111/j.1442-2042.2008.02136.x.
In order to clinically investigate the mechanism of ejaculatory dysfunction attributable to the alpha1-blocker silodosin, a real-time observation of ejaculation by healthy males was performed.
Following intake of silodosin, a newly developed selective alpha1-blocker for benign prostatic hypertrophy, ejaculation was dynamically observed using color Doppler ultrasound in three healthy males. Normal ejaculation was also investigated in the same manner.
With silodosin intake, no antegrade ejaculation was observed in cases 1 or 2. In case 1, seminal fluid slowly but continuously flowed out from the seminal vesicles into the bladder. In case 2, only a small amount of seminal fluid flowed into the bladder during the ejaculatory sensation. In case 3, ejection of a small amount of semen from the external urethral orifice was observed and inflow of a small amount of seminal fluid into the bladder was also captured. Without silodosin intake, all three subjects exhibited antegrade ejaculation.
The mechanism of ejaculatory dysfunction is intricately related to retrograde ejaculation (retrograde inflow of seminal fluid), insufficient contraction of the seminal vesicles, and insufficient rhythmic contraction of the muscles of the pelvic floor.
为了临床研究α1受体阻滞剂西洛多辛所致射精功能障碍的机制，对健康男性的射精过程进行了实时观察。
在摄入西洛多辛（一种新开发的用于治疗良性前列腺增生的选择性α1受体阻滞剂）后，使用彩色多普勒超声对三名健康男性的射精过程进行动态观察。同时也以同样的方式对正常射精进行了研究。
摄入西洛多辛后，病例1和病例2未观察到顺行射精。病例1中，精液缓慢但持续地从精囊流入膀胱。病例2中，在射精感觉期间只有少量精液流入膀胱。病例3中，观察到少量精液从尿道口射出，同时也捕捉到少量精液流入膀胱。未摄入西洛多辛时，三名受试者均表现为顺行射精。
射精功能障碍的机制与逆行射精（精液逆行流入）、精囊收缩不足以及盆底肌肉节律性收缩不足密切相关。
