Takahashi Toku, Matsuda Kenichi, Kono Toru, Pappas Theodore N
Department of Surgery, Duke University Medical Center, Durham, NC 27705, USA.
Intensive Care Med. 2003 Feb;29(2):309-11. doi: 10.1007/s00134-002-1580-3. Epub 2002 Dec 11.
Although it has been demonstrated that hyperglycemia inhibits gastrointestinal (GI) motility, its inhibitory mechanism remains unclear.
Electrophysiological study.
As GI motility is under the influence of the vagus, we studied the effects of hyperglycemia on neural activity of the dorsal motor nucleus of vagi (DMV) in anesthetized rats.
A tungsten electrode was placed in the left side of the DMV area and extracellular electrical signals from the electrode were recorded. Single unit nerve activity was identified by the discriminator. D-glucose infusion elevated the peripheral blood glucose concentration from 3.4-5.9 mm to 12.0-21.8 mm and the neural firing of the DMV was significantly reduced by D-glucose infusion. After the 30 min D-glucose infusion, saline was re-infused for 90 min. Blood glucose level returned to 6.5-7.8 m m and the neural firing partially recovered 90 min after the saline re-infusion. There was a significant negative correlation observed between the counts of neural spikes and blood glucose concentrations ( r=0.84, p<0.01).
It is suggested that hyperglycemia impairs GI motility by inhibiting vagal efferent activity. A recent study in intensive care unit (ICU) patients demonstrated that uncontrolled hyperglycemia is associated with poor outcomes. We propose that glycemia control is crucial in ICU patients to maintain the GI motility and vagus nerve activity.
尽管已有研究表明高血糖会抑制胃肠（GI）蠕动，但其抑制机制仍不清楚。
电生理研究。
由于胃肠蠕动受迷走神经影响，我们研究了高血糖对麻醉大鼠迷走神经背核（DMV）神经活动的影响。
将一根钨电极置于DMV区域左侧，记录来自该电极的细胞外电信号。通过鉴别器识别单单位神经活动。静脉输注D-葡萄糖使外周血糖浓度从3.4 - 5.9 mmol/L升高至12.0 - 21.8 mmol/L，D-葡萄糖输注使DMV的神经放电显著减少。在输注30分钟D-葡萄糖后，重新输注生理盐水90分钟。血糖水平恢复至6.5 - 7.8 mmol/L，在重新输注生理盐水90分钟后神经放电部分恢复。神经尖峰计数与血糖浓度之间存在显著负相关（r = 0.84，p < 0.01）。
提示高血糖通过抑制迷走神经传出活动损害胃肠蠕动。近期一项针对重症监护病房（ICU）患者的研究表明，血糖控制不佳与不良预后相关。我们建议，在ICU患者中控制血糖对于维持胃肠蠕动和迷走神经活动至关重要。
