Ruckebusch Y, Roger T
Department of Physiology, National Veterinary School, Toulouse, France.
J Vet Pharmacol Ther. 1988 Dec;11(4):322-9. doi: 10.1111/j.1365-2885.1988.tb00191.x.
The electromyogram of the terminal ileum, the caecum and the proximal right ventral colon was recorded in fasted conscious ponies receiving intravenously equiactive doses of pilocarpine (0.05 mg/kg) and carbachol (0.01 mg/kg) as acetylcholine analogues; cisapride (0.1 mg/kg) and metoclopramide (2 mg/kg) facilitating acetylcholine release from myenteric neurones and naloxone (0.05 mg/kg) as an antagonist of the endogenous inhibitory opioid system. Both cisapride and naloxone induced typical migrating spike bursts in the colon associated with contractions of caecal body and caecal base. Both pilocarpine and carbachol stimulated the terminal ileum but had opposite effects on the activity of the caeco-colonic segment which was decreased by pilocarpine and increased by carbachol. High doses of metoclopramide had weak and unspecific stimulatory motor effects. It is concluded that a true prokinetic effect at the equine ileo-caeco-colonic junction requires a motor profile which includes coordination between contractions sequentially involving the body and the base of the caecum and migrating spike bursts on the proximal colon. Such changes in the motor profile were produced by cisapride and naloxone and to a lesser extent by carbachol.
在禁食的清醒小马中记录回肠末端、盲肠和右腹侧近端结肠的肌电图，这些小马静脉注射等活性剂量的毛果芸香碱（0.05毫克/千克）和卡巴胆碱（0.01毫克/千克）作为乙酰胆碱类似物；西沙必利（0.1毫克/千克）和甲氧氯普胺（2毫克/千克）促进乙酰胆碱从肌间神经元释放，纳洛酮（0.05毫克/千克）作为内源性抑制性阿片系统的拮抗剂。西沙必利和纳洛酮均在结肠诱导典型的移行性棘波爆发，伴有盲肠体和盲肠基部的收缩。毛果芸香碱和卡巴胆碱均刺激回肠末端，但对盲肠-结肠段的活动有相反作用，毛果芸香碱使其活动降低，卡巴胆碱使其活动增加。高剂量的甲氧氯普胺具有微弱且非特异性的刺激运动作用。得出的结论是，在马的回肠-盲肠-结肠连接处真正的促动力作用需要一种运动模式，该模式包括依次涉及盲肠体和盲肠基部的收缩之间的协调以及近端结肠上的移行性棘波爆发。西沙必利和纳洛酮产生了这种运动模式的变化，卡巴胆碱在较小程度上也产生了这种变化。
