Shafik A
Department of Surgery and Research, Faculty of Medicine, Cairo University, Egypt.
J Surg Res. 1995 Oct;59(4):441-5. doi: 10.1006/jsre.1995.1188.
The effect of inferior rectal nerve (IRN) stimulation on sphincteric control of the rectal neck was studied in eight dogs. With the dog under anesthesia, the IRN was exposed through para-anal incision, and a bipolar electrode was applied to it. Response of the rectal and rectal neck pressures as well as external and sphincter (EAS) EMG activity to IRN stimulation was determined. IRN stimulation resulted in increase in both the rectal neck pressure (P < 0.01) and the EMG activity of EAS (P < 0.01). Response increased with increasing stimulation frequency up to 50 Hz, above which no more response occurred. Rectal pressure showed no change (P > 0.05). Both the latency and the duration of response decreased with increased stimulation. The response was resumed after an off-time of twice the stimulation phase. Long-term activation has not been associated with an impairment of nerve responsiveness or with electrode migration or break. To conclude, a stimulus of 50 Hz evokes the most adequate EAS contraction and RN pressure elevation. Chronic electrostimulation of the perineal nerve may restore EAS tone.
在八只狗身上研究了直肠下神经（IRN）刺激对直肠颈部括约肌控制的影响。在狗麻醉状态下，通过肛门旁切口暴露IRN，并将双极电极应用于其上。测定了直肠和直肠颈部压力以及外括约肌（EAS）肌电图活动对IRN刺激的反应。IRN刺激导致直肠颈部压力增加（P < 0.01）和EAS肌电图活动增加（P < 0.01）。随着刺激频率增加至50Hz，反应增强，超过该频率则不再有反应。直肠压力无变化（P > 0.05）。反应的潜伏期和持续时间随刺激增加而缩短。在刺激阶段的两倍间歇时间后反应恢复。长期激活未与神经反应性受损、电极迁移或断裂相关。总之，50Hz的刺激引起最适当的EAS收缩和直肠颈部压力升高。会阴神经的慢性电刺激可能恢复EAS张力。
