Buret A, Hardin J A, Olson M E, Gall D G
Department of Paediatrics, University of Calgary, Alberta, Canada.
Gastroenterology. 1992 Aug;103(2):506-13. doi: 10.1016/0016-5085(92)90840-u.
Mongolian gerbils were infected with a human pathogenic Giardia lamblia strain and compared with sham-treated control animals 6 days after inoculation. Infection resulted in crypt hyperplasia associated with an increased enterocyte migration rate. Villus height was decreased in the duodenum, unchanged in the jejunum, and increased in the ileum of infected animals. Epithelial microvilli were markedly shortened, and brush border surface area decreased in the jejunum and ileum of infected animals. Thymidine kinase activity was increased in isolated duodenal villus enterocytes but did not differ in the jejunum and ileum. In vitro and in vivo experiments showed that the infection resulted in decreased jejunal glucose-stimulated electrolyte, water, and 3-O-methyl-D-glucose absorption, whereas in the ileum in vitro electrolyte and 3-O-methyl-D-glucose absorption was similar in infected and control animals. Thus, in the jejunum infection causes electrolyte, solute, and fluid malabsorption associated with decreased brush border surface area. The results indicate that the diarrhea associated with giardiasis is caused by malabsorption rather than active secretion.
将蒙古沙鼠感染一株人致病性蓝氏贾第鞭毛虫，并在接种6天后与假处理的对照动物进行比较。感染导致隐窝增生，并伴有肠上皮细胞迁移率增加。感染动物的十二指肠绒毛高度降低，空肠绒毛高度无变化，回肠绒毛高度增加。感染动物空肠和回肠的上皮微绒毛明显缩短，刷状缘表面积减小。分离的十二指肠绒毛肠上皮细胞中胸苷激酶活性增加，但空肠和回肠中无差异。体外和体内实验表明，感染导致空肠葡萄糖刺激的电解质、水和3 - O - 甲基 - D - 葡萄糖吸收减少，而在回肠，感染动物和对照动物的体外电解质和3 - O - 甲基 - D - 葡萄糖吸收相似。因此，在空肠中，感染导致与刷状缘表面积减小相关的电解质、溶质和液体吸收不良。结果表明，贾第虫病相关的腹泻是由吸收不良而非主动分泌引起的。
