Holzer P, Barthó L, Lippe I T, Petritsch W, Leb G
Regul Pept. 1986 Dec 30;16(3-4):305-14. doi: 10.1016/0167-0115(86)90030-3.
The effect of porcine pancreatic polypeptide (PP) on the motor activity of the longitudinal and circular muscles of the guinea-pig isolated small intestine was investigated. PP (0.2-20 nM) inhibited cholinergic contractions of the longitudinal muscle in response to electrical field stimulation, the maximal effect being a 30% reduction of the contraction amplitude. Carbachol-induced contractions of the longitudinal muscle were not affected by PP (10 nM). PP (0.3-30 nM) also inhibited reflex contractions of the circular muscle elicited by balloon distension and recorded orally to the site of distension; the maximal effect was a 80% reduction of the reflex contraction. In contrast, carbachol-induced contractions of the circular muscle remained unaltered by PP (10 nM). It was further found that PP (10 and 100 nM) enhanced the threshold intraluminal pressure at which peristaltic waves were triggered. All these effects of PP appeared to be transient. Taken together, these data indicate that PP does not act on intestinal smooth muscle but can modulate the activity of certain enteric neurones which are involved in the regulation of intestinal motility.
研究了猪胰多肽(PP)对豚鼠离体小肠纵行肌和环行肌运动活性的影响。PP(0.2 - 20 nM)抑制电场刺激引起的纵行肌胆碱能收缩,最大效应是使收缩幅度降低30%。卡巴胆碱诱导的纵行肌收缩不受PP(10 nM)影响。PP(0.3 - 30 nM)还抑制球囊扩张引起的环行肌反射性收缩,并在扩张部位口侧记录;最大效应是使反射性收缩降低80%。相反,卡巴胆碱诱导的环行肌收缩不受PP(10 nM)影响。进一步发现,PP(10和100 nM)提高了触发蠕动波的腔内阈值压力。PP的所有这些效应似乎都是短暂的。综上所述,这些数据表明PP并不作用于肠道平滑肌,而是可以调节某些参与肠道运动调节的肠神经元的活性。