Grundy D, Hillsley K, Kirkup A J, Richards W
Dept. of Biomedical Science, University of Sheffield, UK.
Dtsch Tierarztl Wochenschr. 1998 Dec;105(12):466-8.
The present electrophysiological investigation examines the effect of CCK and 5-hydroxytryptamine on gastrointestinal afferent fibre discharge. 5-HT markedly stimulated mesenteric afferents. The response was transient (< 10s) and mediated by 5-HT3 receptors as demonstrated by the action of 2-methyl-5-HT and antagonism by granisetron. CCK was also a potent stimulus to mesenteric afferents causing a long-lasting (> 30s) increase in excitability. The response to CCK was mediated via the CCKA receptor as shown by the antagonistic action of devazepide. At doses of granisetron and devazepide which completely block the response to exogenous 5-HT and CCK, the afferent fibres still responded to both mechanical and chemical stimulation of the mucosa. Thus products of enteroendocrine cells can have profound effects on mucosal afferent sensitivity but do not play an obligatory role in afferent signal transduction.
本电生理研究考察了胆囊收缩素（CCK）和5-羟色胺对胃肠传入纤维放电的影响。5-羟色胺（5-HT）显著刺激肠系膜传入神经。该反应是短暂的（<10秒），且由5-HT3受体介导，2-甲基-5-HT的作用及格拉司琼的拮抗作用证明了这一点。CCK也是肠系膜传入神经的有效刺激物，可导致兴奋性持续较长时间（>30秒）增加。如地伐西匹的拮抗作用所示，对CCK的反应是通过CCKA受体介导的。在完全阻断对外源性5-HT和CCK反应的格拉司琼和地伐西匹剂量下，传入纤维仍对黏膜的机械和化学刺激产生反应。因此，肠内分泌细胞的产物可对黏膜传入敏感性产生深远影响，但在传入信号转导中不发挥必需作用。
