Sato D, Lai Z F, Tokutomi N, Tokutomi Y, Maeda H, Nishikawa S, Nishikawa S, Ogawa M, Nishi K
Department of Pharmacology, Kumamoto University, School of Medicine, Japan.
Am J Physiol. 1996 Nov;271(5 Pt 1):G762-71. doi: 10.1152/ajpgi.1996.271.5.G762.
We examined developmental changes in responses of the isolated segment of the ileum of BALB/c mice treated with a monoclonal antibody (ACK2) to the receptor tyrosine kinase (Kit) for 4 days postnatally to pharmacological agents in vitro. Rhythmic contraction and relaxation of the isolated ileum started to appear on day 4 postpartum, and the sensitivity to acetylcholine (ACh) decreased gradually after birth. Treatment with ACK2 induced augmentation of contractile responses and receptor sensitivity of the longitudinal muscle of the ileum to ACh, bradykinin, and prostaglandin F2 alpha. ACh induced larger depolarization in smooth muscle cells of the ileum in the ACK2-treated mice than in the control. Circular muscle responses to these substances, as measured by changes in intraluminal pressure, were not altered by ACK2 treatment. Results suggest that interstitial cells play an important role not only in the development of the pacemaking system of the small intestine but also in the functional development of the contractile properties of the intestinal smooth muscle.
我们研究了出生后用单克隆抗体（ACK2）处理4天的BALB/c小鼠回肠离体段对受体酪氨酸激酶（Kit）的反应在体外对药理剂的发育变化。离体回肠的节律性收缩和舒张在出生后第4天开始出现，并且出生后对乙酰胆碱（ACh）的敏感性逐渐降低。用ACK2处理可诱导回肠纵肌对ACh、缓激肽和前列腺素F2α的收缩反应增强以及受体敏感性增加。在经ACK2处理的小鼠中，ACh在回肠平滑肌细胞中诱导的去极化比对照组更大。通过腔内压力变化测量，回肠环肌对这些物质的反应未因ACK2处理而改变。结果表明，间质细胞不仅在小肠起搏系统的发育中起重要作用，而且在肠道平滑肌收缩特性的功能发育中也起重要作用。
