Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.108 (lactase)
 2,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The postnatal development of the gastric mucosa was observed in Long Evans rats. In both pyloric and fundic mucosae, the mitotic index peaked at 5 days of age and then gradually decreased to reach a constant level from 14 days of age onward (P less than 0.05), the germinal region shifted from the deeper area of the mucosae upward to the middle layer. The number of parietal cells increased gradually (P less than 0.05). Gastric pH on the mucosal surface decreased from 6 on the day of birth to about 4 at 7 days of age and to about 2 at 28 days of age. The inverse relationship between the number of parietal cells and pH value on gastric mucosa was found to be highly significant (P less than 0.01). Trehalase and sucrase activities were observed at 7 days of age and lactase and maltase activities from 0 to 14 days of age. In the pyloric mucosae, foveolae containing goblet cells which were positive for Alcian blue-PAS and HID were observed between 0 and 7 days of age. These cells disappeared by 14 days of age concurrently with the decrease in pH value and increase in the number of parietal cells.
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PMID:pH-related differentiation in the epithelia of the gastric mucosa of postnatal rats. 403 97

These studies examined the potential for reorganization and differentiation of dissociated 18-day fetal rat intestine. Cultures of trypsin-dissociated fetal intestine were maintained in vitro for 1 week on a three-dimensional matrix, then transplanted into syngeneic hosts. When harvested after 4 weeks, these transplants consistently demonstrated organotypic differentiation. Spherical structures containing crypts with frequent mitotic figures and villi lined with columnar epithelium had formed. PAS staining demonstrated positive epithelial cell brush borders, goblet cells, and luminal contents. Significant levels of the microvillus membrane enzymes lactase, sucrase, maltase, and alkaline phosphatase were present in the luminal contents. Sucrase-isomaltase, an enzyme characteristic of postweaning small intestine, was demonstrated by immunoprecipitation and SDS-PAGE. Thus, both morphological and biochemical maturation occurred in the transplants.
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PMID:Organotypic differentiation of trypsin-dissociated fetal rat intestine. 661 90