Schwörer H, Racké K, Kilbinger H
Department of Pharmacology, University of Mainz, Federal Republic of Germany.
Naunyn Schmiedebergs Arch Pharmacol. 1989 May;339(5):540-5. doi: 10.1007/BF00167258.
Isolated segments of the guinea pig small intestine were vascularly perfused and the release of endogenous serotonin (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) into the portal vein was measured. All test substances were intraarterially perfused. Vasoactive intestinal polypeptide (VIP, 1 pmol/l-100 nmol/l) inhibited the spontaneous release of 5-HT and 5-HIAA. The maximal inhibitory effect (about 60%) was seen at 100 pmol/l. The effect of VIP on the spontaneous release of 5-HT and 5-HIAA was not changed in the presence of 1 mumol/l tetrodotoxin (TTX). Raising intraluminal pressure by 500 Pa for 5 min increased the release of 5-HT and 5-HIAA by about 25%. Raising the intraluminal pressure in the presence of VIP reduced the release of 5-HT and 5-HIAA by about 75%. In the presence of TTX (1 mumol/l), raising intraluminal pressure also caused a decrease of the release of 5-HT and 5-HIAA which was unaffected by the additional presence of VIP. The fluid volume expelled during peristaltic activity was not affected by VIP, but reduced by about 90% in the presence of TTX. In conclusion the results demonstrate a direct inhibitory effect of VIP on the release of 5-HT from the enterochromaffin cells. In addition, VIP appears to interfere with the neuronally mediated stimulation of 5-HT release during peristaltic activity.
对豚鼠小肠的分离节段进行血管灌注，并测量内源性血清素（5-羟色胺，5-HT）及其代谢产物5-羟吲哚乙酸（5-HIAA）向门静脉的释放量。所有受试物质均通过动脉进行灌注。血管活性肠肽（VIP，1皮摩尔/升 - 100纳摩尔/升）抑制5-HT和5-HIAA的自发释放。在100皮摩尔/升时可观察到最大抑制作用（约60%）。在存在1微摩尔/升河豚毒素（TTX）的情况下，VIP对5-HT和5-HIAA自发释放的作用未发生改变。将腔内压力提高500帕5分钟可使5-HT和5-HIAA的释放量增加约25%。在存在VIP的情况下提高腔内压力可使5-HT和5-HIAA的释放量减少约75%。在存在TTX（1微摩尔/升）的情况下，提高腔内压力也会导致5-HT和5-HIAA释放量减少，且不受额外存在的VIP的影响。蠕动活动期间排出的液体量不受VIP影响，但在存在TTX的情况下减少约90%。总之，结果表明VIP对肠嗜铬细胞释放5-HT具有直接抑制作用。此外，VIP似乎会干扰蠕动活动期间神经元介导的5-HT释放刺激。
