Yu X, Tu L, Lei P, Song J, Xu H, Hou X
Department of Gastroenterology, Wuhan Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Neurogastroenterol Motil. 2014 Jul;26(7):1049-56. doi: 10.1111/nmo.12362.
The aims of this study were to investigate the effect of gastric electrical stimulation (GES) with different parameters on emesis induced by apomorphine, and possible center mechanisms by brain functional magnetic resonance imaging (fMRI).
Six dogs implanted with electrodes on gastric serosa were used in this study. Part 1: Apomorphine was injected in the control session and GES sessions. GESs with different parameters were applied in GES session. Gastric slow waves and emesis and behaviors suggestive of nausea were recorded in each session. Part 2: Each dog was anesthetized and given GESs with different parameters or sham stimulation for 15 min after baseline (5 min), respectively. The location of cerebral activation induced by GES was investigated by fMRI.
Apomorphine induced emesis and behaviors suggestive of nausea, and gastric dysrhythmia. The emesis frequency in control session was 5.5 ± 0.99, and symptoms score was 22.17 ± 1.01. GES with short pulse and long pulse could not improve emesis and symptoms induced by apomorphine. The emesis frequency (4.5 ± 0.76 in short pulse and 6.33 ± 1.05 in long pulse) and symptoms scores had no significant difference compared to control session (each p > 0.05). GES with trains of short pulse reduced emesis time frequency (3.83 ± 0.7, p = 0.042 vs control) and symptoms score (p = 0.037 vs control) obviously. Brain fMRI showed that GES with short pulse and long pulse activated brain stem region, and trains of short pulse made amygdala and occipital lobe activation.
CONCLUSIONS & INFERENCES: Apomorphine induced emesis and gastric dysrhythmia. GES with trains of short pulses relieves emetic responses through activation of amygdala region.
本研究旨在探讨不同参数的胃电刺激（GES）对阿扑吗啡诱导呕吐的影响，以及通过脑功能磁共振成像（fMRI）研究其可能的中枢机制。
本研究使用6只在胃浆膜植入电极的犬。第一部分：在对照期和胃电刺激期注射阿扑吗啡。在胃电刺激期应用不同参数的胃电刺激。记录每期的胃慢波、呕吐及提示恶心的行为。第二部分：每只犬在基线（5分钟）后分别接受不同参数的胃电刺激或假刺激15分钟，麻醉状态下进行。通过fMRI研究胃电刺激诱导的脑激活位置。
阿扑吗啡诱导呕吐及提示恶心的行为，以及胃节律紊乱。对照期呕吐频率为5.5±0.99，症状评分为22.17±1.01。短脉冲和长脉冲胃电刺激不能改善阿扑吗啡诱导的呕吐和症状。短脉冲（4.5±0.76）和长脉冲（6.33±1.05）的呕吐频率及症状评分与对照期相比无显著差异（各p>0.05）。短脉冲串胃电刺激明显降低呕吐时间频率（3.83±0.7，与对照相比p=0.042）和症状评分（与对照相比p=0.037）。脑fMRI显示，短脉冲和长脉冲胃电刺激激活脑干区域，短脉冲串使杏仁核和枕叶激活。
阿扑吗啡诱导呕吐和胃节律紊乱。短脉冲串胃电刺激通过激活杏仁核区域减轻呕吐反应。
