Gulia K K, Jodo E, Kawauchi A, Miki T, Kayama Y, Mallick H N, Koyama Y
Department of Neurophysiology, Fukushima Medical University School of Medicine, Fukushima, Japan.
Neuroscience. 2008 Oct 28;156(4):1064-73. doi: 10.1016/j.neuroscience.2008.08.032. Epub 2008 Aug 27.
The effects of electrical stimulation to the septum on penile erections in rats were examined to clarify the mechanisms for regulation of erectile responses during different states of vigilance. Penile responses were assessed by changes in pressure in the corpus spongiosum of penis (CSP) and electromyography (EMG) of the bulbospongiosus (BS) muscle. In anesthetized and un-anesthetized rats, stimulation in and around the septum induced three erectile patterns; 1) a Normal type response, which was indistinguishable from a spontaneous erection, characterized by a slow increase in CSP pressure with sharp CSP pressure peaks associated with BS muscle bursts, 2) Mixed type response, in which high frequency CSP pressure peaks were followed by a Normal type response, and 3) a Prolonged type response, evoked only in the anesthetized rat, consisting of a single sharp CSP peak followed by a slow increase in CSP pressure and a return to baseline with multiple subsequent events repeated for up to 960 s. In addition, a Micturition type response was also observed involving high frequency CSP pressure oscillations similar to the pressure pattern seen during spontaneous micturition. We found that erections were induced after stimulation to the lateral septum (LS), but not from the medial septum (MS). In anesthetized rats, a few responses were also obtained following stimulation of the horizontal limb of diagonal band (HDB). In un-anesthetized rats, responses were also induced from the HDB and the ventral limb of diagonal band (VDB) and the adjoining areas. The effective sites for eliciting erection during rapid eye movement (REM) sleep were located in the dorsal and intermediate parts of the LS, whereas the ventral part of the LS was the most effective site for eliciting erections during wakefulness. These results suggest a functional role for penile erection in the septum, and further suggest that subdivisions of the LS may have different roles in the regulation of penile erection during wakefulness and REM sleep.
研究电刺激大鼠隔膜对阴茎勃起的影响，以阐明不同警觉状态下勃起反应的调节机制。通过阴茎海绵体（CSP）压力变化和球海绵体（BS）肌肌电图（EMG）评估阴茎反应。在麻醉和未麻醉的大鼠中，刺激隔膜及其周围诱发了三种勃起模式：1）正常型反应，与自发勃起无异，其特征是CSP压力缓慢升高，伴有与BS肌爆发相关的尖锐CSP压力峰值；2）混合型反应，高频CSP压力峰值后接正常型反应；3）延长型反应，仅在麻醉大鼠中诱发，由单个尖锐CSP峰值后接CSP压力缓慢升高并恢复至基线，随后多次重复该事件，持续长达960秒。此外，还观察到排尿型反应，涉及高频CSP压力振荡，类似于自发排尿时的压力模式。我们发现，刺激外侧隔膜（LS）后可诱发勃起，但刺激内侧隔膜（MS）则不能。在麻醉大鼠中，刺激斜角带水平支（HDB）后也获得了一些反应。在未麻醉大鼠中，HDB、斜角带腹支（VDB）及其相邻区域也可诱发反应。快速眼动（REM）睡眠期间诱发勃起的有效部位位于LS的背侧和中间部分，而LS的腹侧部分是清醒时诱发勃起的最有效部位。这些结果表明隔膜在阴茎勃起中具有功能作用，进一步表明LS的细分在清醒和REM睡眠期间阴茎勃起的调节中可能具有不同作用。
