期刊名称:Journal of Nutritional Science and Vitaminology
印刷版ISSN:0301-4800
电子版ISSN:1881-7742
出版年度:1980
卷号:26
期号:2
页码:171-182
DOI:10.3177/jnsv.26.171
出版社:Center for Academic Publications Japan
摘要:Appearance of immunoreactive sucrase-isomaltase complex was observed in rat small intestine during postnatal development and maturation along the villus-crypt axis by single radial immunodiffusion. The immunoreactive sucrase-isomaltase complex in brush-border membrane increased in parallel with enzyme activities until weaning. After weaning, higher amounts of the immunoreactive enzyme proteins were found as compared with their activities. On the other hand, during cell maturation in adult rat jejunum, the immunoreactive enzyme proteins increased with the activities of sucrase-isomaltase complex. However, a significant amount of the immunoreactive enzyme proteins was observed in the crypt cells with low enzyme activities. Chromatographic profiles on Sephadex G-200 column of the sucrase-isomaltase complex in the upper villus and crypt cells did not change. From these results, it is suggested that the appearance of sucrase and isomaltase activities until weaning is ascribed to the synthesis of an active sucrase-isomaltase complex or the synthesis of an inactive proenzyme followed by rapid conversion to active enzyme, and during cell maturation, it is caused by the synthesis of the inactive proenzyme in the crypt cells followed by its activation in the villus cells.