Role of epithelial-mesenchymal interactions in the ontogenesis of intestinal brush-border enzymes

摘要: The respective roles of embryonic intestinal mesenchyme and endoderm in the biochemical differentiation brushborder enzymes have been investigated. As a first step this study, prenatal developmental pattern several (maltase, sucrase, lactase, alkaline phosphatase), measured brush-border membranes purified from chick rat intestine, has established. Xenoplastic recombinations between tissue components 5-12-day-old embryos 14-day-old fetal rats performed. After 11 days intracoelomic graft 3-day-old embryos, combinations composed (Cm/Re) showed enzyme activities characteristic intestine: high lactase activity traces sucrase activity. inverse (Rm/Ce) exhibited chicken-like pattern: In latter combinations, specific were similar to those present intestine 15- 16-day-old (theoretical level reached after grafting period). Conversely, levels Cm/Re remained lower than normally developed intestine. These results show that endodermal carries characteristics its future differentiation. They also suggest important maturation events, which occur shortly before birth rat, are dependent upon other factors, presumably hormones.