Adrian T E, Bloom S R, Edwards A V
J Physiol. 1983 Nov;344:25-35. doi: 10.1113/jphysiol.1983.sp014921.
Effects of stimulation of the peripheral ends of the vagus nerves below the heart at 4 Hz continuously, and at 40 Hz for 1 s at 10 s intervals, have been compared in conscious calves below behavioural threshold. Neither pattern of stimulation caused any significant change in mean aortic blood pressure or heart rate but both invariably produced a substantial increase in the flow of intestinal lymph. Each form of stimulation provoked release of glucagon, insulin and pancreatic polypeptide from the pancreas and produced a small but significant rise in mean arterial plasma glucose concentration. The release of gastric inhibitory peptide- and bombesin-like molecules from the gastrointestinal tract was not affected by vagal stimulation whereas release of vasoactive intestinal peptide was observed in response to both patterns of vagal stimulation. Evidence was obtained to suggest that gastrin-like peptides are preferentially released into the bloodstream whereas cholecystokinin-like peptides are not. Vagal stimulation releases somatostatin from the gastrointestinal tract but discontinuous stimulation seems to inhibit the release of somatostatin into the general circulation. The results that have been obtained, employing this particular protocol, suggest that the pattern of the stimulus that is applied to the vagal splanchnic innervation has relatively little effect on neuroendocrine response in this species.
在行为阈值以下的清醒小牛中，比较了以4Hz持续刺激心脏下方迷走神经外周端，以及以40Hz每隔10s刺激1s的效果。两种刺激模式均未引起平均主动脉血压或心率的任何显著变化，但都始终导致肠淋巴流量大幅增加。每种刺激形式都会引起胰腺释放胰高血糖素、胰岛素和胰多肽，并使平均动脉血浆葡萄糖浓度小幅但显著升高。迷走神经刺激不影响胃肠道中胃抑制肽和蛙皮素样分子的释放，而两种迷走神经刺激模式均能引起血管活性肠肽的释放。有证据表明，胃泌素样肽优先释放到血液中，而胆囊收缩素样肽则不然。迷走神经刺激会使胃肠道释放生长抑素，但间断刺激似乎会抑制生长抑素释放到全身循环中。采用这种特定方案所获得的结果表明，施加于迷走神经内脏神经支配的刺激模式对该物种的神经内分泌反应影响相对较小。
