Clément Pierre, Kia Hossein K, Droupy Stephane, Bernabe Jacques, Alexandre Laurent, Denys Pierre, Giuliano François
Pelvipharm Laboratories, Campus CNRS, Gif-sur-Yvette, Framce.
J Androl. 2006 May-Jun;27(3):381-9. doi: 10.2164/jandrol.05163. Epub 2006 Feb 1.
The occurrence of ejaculation, which consists of 2 distinct phases (emission and expulsion), requires a tight coordination of peripheral autonomic and somatic nerves. However, some aspects of the mechanism of ejaculation are not clearly defined. To clarify this issue, we used the p-chloroamphetamine (PCA)-induced ejaculation model in anesthetized rats and investigated the effects of selective peripheral nerves lesions on seminal vesicle and bulbospongiosus (BS) muscle activities as representing physiological markers of emission and expulsion phases, respectively. In intact rats, ejaculation induced with PCA (intraperitoneal 5 mg/kg) correlated with coordinated increases in seminal vesicle pressure (SVP) and BS electromyographic activity. PCA-induced ejaculation was still observed in rats with bilateral lesion of hypogastric nerves (HNx), lumbar paravertebral sympathetic chain (LSCx), or dorsal nerves of the penis (DNPx). Conversely, bilateral section of pelvic nerves (PNx) or L6-S1 dorsal roots (DRx) abolished PCA-induced ejaculation. The amplitude of SVP increases induced by PCA was reduced in PNx, HNx, and LSCx rats, whereas it was unchanged in DRx and DNPx rats. The time interval between SVP increases and BS muscle contractions induced by PCA was comparable in the different neural lesion groups. In conclusion, PCA initiates both emission and expulsion independently from each other. In this model, afferents conveyed by the pelvic nerves appear to be unnecessary for occurrence of BS muscle contractions but are essential for a complete ejaculatory response.
射精由两个不同阶段（排精和射精）组成，其发生需要外周自主神经和躯体神经的紧密协调。然而，射精机制的某些方面尚未明确界定。为阐明这一问题，我们在麻醉大鼠中使用对氯苯丙胺（PCA）诱导的射精模型，分别研究了选择性外周神经损伤对精囊和球海绵体（BS）肌肉活动的影响，将其作为排精和射精阶段的生理标志物。在完整大鼠中，PCA（腹腔注射5mg/kg）诱导的射精与精囊压力（SVP）和BS肌电图活动的协同增加相关。在双侧腹下神经损伤（HNx）、腰旁交感神经链损伤（LSCx）或阴茎背神经损伤（DNPx）的大鼠中仍可观察到PCA诱导的射精。相反，双侧切断盆神经（PNx）或L6-S1背根（DRx）可消除PCA诱导的射精。PCA诱导的SVP增加幅度在PNx、HNx和LSCx大鼠中降低，而在DRx和DNPx大鼠中不变。PCA诱导的SVP增加与BS肌肉收缩之间的时间间隔在不同神经损伤组中相当。总之，PCA独立启动排精和射精。在该模型中，盆神经传导的传入神经似乎对BS肌肉收缩的发生不是必需的，但对完整的射精反应至关重要。
