Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.26 (invertase)
 4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To determine whether serum and mucosal DAO activity reflects quantitative changes in the small bowel mucosal mass, we have chosen an experimental model of mucosal hyperplasia which is known to occur in the rat after enterectomy. A 50% proximal enterectomy or a single transection was performed in 20 growing rats weighing 145-160 g. Ten days following surgery, we determined mucosal mass parameters (weight, protein, and DNA content), sucrase activity, and DAO activity in the duodenum (segment A), proximal ileum (segment B), and distal ileum (segment C) of the remaining small intestine. Mucosal hyperplasia was demonstrated by the finding that in each segment, mucosal weight, protein, and DNA content per centimeter of gut length were significantly (P less than 0.01) higher (+38 to + 78%) in the resected group than in transected controls. In segments B and C of resected rats, the changes in DAO activity expressed per gram of mucosa paralleled the changes in mucosal mass, the activity being increased by +69% and +49% (P less than 0.05) compared to the values recorded in transected controls. Expressed per centimeter of gut length, total DAO activity was also enhanced by +141% in segment B (P less than 0.05 vs controls) and by +87% in segment C (P less than 0.01 vs controls) of resected rats. In the duodenum, the changes in DAO activity were small (+36%) and not significant.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Changes in serum and intestinal diamine oxidase (DAO) activity after proximal enterectomy in rats. Correlation of DAO activity with mucosal mass parameters. 250 67

To investigate the adaptation of functions expressed by the villous and crypt cell of the intestinal mucosa after intestinal resection, a 50% proximal enterectomy or a single transection was performed in 16 growing rats weighing 175-200 g. Ten days following the enterectomy, we determined the mucosal mass parameters (weight, protein, and DNA content), the activity of microvillous enzymes (lactase, sucrase, and aminopeptidase) in villus cells, and the concentration of the secretory component of immunoglobulins in crypt cells isolated from the proximal intestinal remnant. Mucosal hyperplasia was attested by the finding that mucosal weight, protein, and DNA content per cm of intestinal length were significantly (p less than 0.01) higher (+29 to +48%) in the resected group than in transected controls. The specific activity of lactase, sucrase, and aminopeptidase were significantly (p less than 0.05) lower (-23 to -56%) in villous cells isolated from the intestinal remnant of resected rats compared to controls. Sucrase activity was depressed in each cell fraction of the entire villous-crypt unit resulting in a lower villous to crypt gradient of enzyme activity. Km for the enzyme determined in villous cells was similar in both groups but the Vmax was reduced proportionally to the enzyme activity in the resected group indicating less enzyme per cell. By contrast, the concentration of secretory component measured by an immunoradiometric assay in both villous and crypt cells was significantly (p less than 0.05) increased (+37 to 45%) following proximal enterectomy. Our data indicate that the response of the epithelial cell to intestinal resection varies according to the metabolic function and that the mechanism of adaptation at the cellular level is complex.
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PMID:Cellular adaptation of the rat small intestine after proximal enterectomy: changes in microvillous enzymes and in the secretory component of immunoglobulins. 311 6