Vermillion D L, Collins S M
Intestinal Diseases Research Unit, McMaster University, Hamilton, Ontario, Canada.
Am J Physiol. 1988 Jan;254(1 Pt 1):G124-9. doi: 10.1152/ajpgi.1988.254.1.G124.
We examined in vitro changes in contractility of jejunal longitudinal muscle strips in rats infected with the nematode parasite Trichinella spiralis. Length-passive tension relationships were unchanged. However, muscle from infected rats on days 5 and 6 postinfection (PI) generated maximal active tension induced by carbachol at significantly less stretch (39.9 +/- 1.0 and 34.3 +/- 6.3%, respectively) than control tissues (66.0 +/- 2.3%). In infected rats on day 5 PI, the maximum tension generated by carbachol (1.6 +/- 0.4 g/mm2) and by 5-hydroxytryptamine (5-HTP) (2.6 +/- 0.1 g/mm2) was significantly greater than in control tissue (0.5 +/- 0.2 g/mm2). On removal of calcium from the medium, responses of muscle from control and infected rats were reduced in a proportionate manner. The increased responsiveness to carbachol and 5-HTP was maximal by day 5 PI and was associated with a decrease in the ED50 value for 5-HTP but not for carbachol. All changes were reversed by 23 days PI. These results indicate that T. spiralis infection in the rat is associated with alterations in jejunal longitudinal smooth muscle function.
我们研究了感染线虫寄生虫旋毛虫的大鼠空肠纵肌条收缩性的体外变化。长度-被动张力关系未改变。然而，感染后第5天和第6天（PI）的感染大鼠肌肉，由卡巴胆碱诱导产生的最大主动张力，在显著小于对照组织（分别为39.9±1.0%和34.3±6.3%）的拉伸程度下即可产生（对照组织为66.0±2.3%）。在感染后第5天的感染大鼠中，卡巴胆碱（1.6±0.4 g/mm²）和5-羟色胺（5-HTP）（2.6±0.1 g/mm²）产生的最大张力显著高于对照组织（0.5±0.2 g/mm²）。从培养基中去除钙后，对照和感染大鼠肌肉的反应以成比例的方式降低。对卡巴胆碱和5-HTP反应性的增加在感染后第5天达到最大，并且与5-HTP的半数有效剂量（ED50）值降低有关，但与卡巴胆碱无关。感染后23天所有变化均逆转。这些结果表明，大鼠感染旋毛虫与空肠纵行平滑肌功能改变有关。
