Shafik A
Department of Surgery and Research, Faculty of Medicine, Cairo University, Egypt.
Urology. 1995 Jul;46(1):85-8. doi: 10.1016/S0090-4295(99)80165-4.
The role of the bulbocavernosus (BC) and ischiocavernosus (IC) muscles in erection and ejaculation was studied.
The response of the urethral and intracorporeal pressure to cavernosus muscle stimulation was evaluated in 18 male volunteers (mean age, 36.6 years). A two-channel microtip catheter was placed in the prostatic and bulbous urethra. Muscle stimulation was done by two needle electrodes inserted into the BC and IC muscles.
BC muscle stimulation caused an increase in the pressure of the bulbous urethra (P < 0.001) and corpus spongiosum (P < 0.01) and an insignificant change in the prostatic and pendulous urethral and corpus cavernosal pressures (difference not significant). IC muscle stimulation effected an increase in the corpus cavernosal pressure (P < 0.001) without changing the urethral pressure (difference not significant).
The BC muscle contracts rhythmically at orgasm and this might help to eject the semen from the posterior to the anterior urethra. It is apparent that the muscle has minimal or no role in erection. IC muscle may have a role in erection by increasing the intracavernosal pressure. It seems that it has no role in ejaculation. BC may be considered the "muscle of ejaculation," and IC the "muscle of erection."
研究球海绵体肌（BC）和坐骨海绵体肌（IC）在勃起和射精过程中的作用。
对18名男性志愿者（平均年龄36.6岁）评估海绵体肌刺激时尿道和海绵体内压力的反应。将双通道微尖导管置于前列腺部和球部尿道。通过插入BC和IC肌的两根针电极进行肌肉刺激。
刺激BC肌导致球部尿道压力升高（P < 0.001）和海绵体压力升高（P < 0.01），而前列腺部、悬垂部尿道及海绵体压力变化不显著（差异无统计学意义）。刺激IC肌使海绵体压力升高（P < 0.001），而尿道压力无变化（差异无统计学意义）。
BC肌在性高潮时有节律地收缩，这可能有助于将精液从后尿道向前尿道排出。显然，该肌肉在勃起过程中作用极小或无作用。IC肌可能通过增加海绵体内压力在勃起中发挥作用。似乎其在射精过程中无作用。BC可被视为“射精肌”，而IC可被视为“勃起肌”。
