5—羟色胺M受体和胆碱能受体阻断剂在红霉素所致小肠动力紊乱和呕吐中的作用

EFFECTS OF CHOLINERGIC AND 5-HT RECEPTOR BLOCKERS ON INCREASED BOWEL MOTIVITY AND EMESIS CAUSED BY ERYTHROMYCIN

本实验对８条犬进行小肠肌电测定，并在记录期间分别静注胆碱能神经阻断剂，阿托品和六甲季胺，以及５－羟色胺（５－ＨＴ）Ｍ受体阻断剂，灭吐灵，以观察其对红霉素所致肠道副作用的影响。结果发现阿托品和六甲季胺不仅能明显地抑制空腹时正常传播性肌电综合波（ＭＭＣ）的发生和传播，降低红霉素促进小肠动力的作用，还能减轻红霉素所致饱腹动物的快波数增加，但对呕吐无明显影响。灭吐灵的实验结果显示红霉素的致吐作用是由５－ＨＴＭ受体介导的，与其促进小肠动力的作用无明显因果关系。

Intestinal myoeleotrical activity in 8 dogs was recorded and analysed by a computer. After 3 hours basal recording either cholinergic blockers, atropine and hexamethonium, or 5-HT M receptor blocker, metoclopramide, was infused for 60 minutes. During the last 30 minutes of the above infusion period erythromycin was simultaneously infused.Results showed that both atropine and hexamethonium decreased pre and post prandial spike activity but did not significantly decrease emesis. Although metoclopramide had no effect on intestinal motility decreased the emeais induoed by a large dose of erthromycin. A small dose of metoclopramide had no effect on emesis but could inhibit emesis induced by apomorphine. We believe that the block effect of large dose metoclopramide was via 5-HTM receptor pathway. The results also showed that no correlation between increased bowel motility and emesis indueed by erythromycin.