Para-chloroamphetamine-induced ejaculation in anaesthetised rat
To induce a complete ejaculatory response in anaesthetised rat. In this model, physiological markers of the emission and expulsion phases of ejaculation induced by the amphetamine derivative para-chloroamphetamine (PCA) can be measured. Contractions of the seminal vesicle and the bulbospongiosus muscle are regarded as physiological markers of, respectively, emission and expulsion phases of ejaculation (figure 1).
Under anaesthesia (isoflurane, urethane or pentobarbital), the carotid artery and the right seminal vesicle are catheterized to measure concomitantly arterial pressure (AP) and seminal vesicle pressure (SVP). Electrical activity of the bulbospongiosus muscle (BS EMG) is also recorded. Physiological markers are monitored before and over 30 min after PCA systemic injection (i.v. or i.p.). Computerized analysis of the recordings is then performed a posteriori using custom-written analysis programs (Sadoc, CNRS, Gif-sur-Yvette, France).
- Number and latency of ejaculations (corresponding to the expulsion of a seminal plug)
- Number, latency, amplitude, duration and area under the curve of SVP increases
- Number, latency, frequency and duration of BS contractions
- Time interval between SVP increase and BS contractions
PCA triggers ejaculation by releasing serotonin and noradrenalin at the spinal level. Therefore, this model is suitable for studying peripheral and spinal modulations of the ejaculatory process and not recommended for investigating supra-spinal modulations.
J Androl (2006) : 27:381-389
Links to applicable Targeted disorders / Pathophysiological models