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)

The effects of deoxycholate, taurocholate and cholate on transport and mucosal ATPase activity have been investigated in the rat jejunum in vivo using closed-loop and perfusion techniques. In the closed-loops, 5 mM deoxycholate selectively inactivated (Na+ + K+)-ATPase, and net secretion of Na+ induced by 2.5 mM deoxycholate was due to reduced lumen to plasma flux of the ion; deoxycholate (2.5 mM) produced marked inhibition of 3-0-methylglucose transport. Luminal disappearance rates of deoxycholate (60.5 plus or minus 2.9% per g wet st of gut) greatly exceeded those of taurocholate (4.3 plus or minus 1.0). In the perfusion studies 1 mM deoxycholate induced net secretion of water, Na+ and C1-, and inhibited active glucose transport; concomitantly "total" ATPase, (Na+ + K+)-ATPase, and Mg-2+-ATPase were inhibited. At higher concentrations (5 mM) deoxycholate stimulated Mg-2+-ATPase activity. Taurocholate and cholate at 1mM had no effect on transport of (Na+ + K+)-ATPase. Mucosal lactase, sucrase and maltase activities were not affected by 1 mM deoxycholate, taurocholate or cholate. These results suggest that deoxycholate inhibits sodium-coupled glucose transport by inhibition of (Na+ + K+)-ATPase at the lateral and basal membranes of the epithelial cell, rather than from an effect at the brush-border membrane level.
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PMID:A comparative study on the effects of different bile salts on mucosal ATPase and transport in the rat jejunum in vivo. 12 87

Sodium-dependent bile acid uptake is developmentally regulated in the rat ileum. Transport activity is abruptly expressed on postnatal d 17, although the mechanisms controlling this expression are poorly understood. Changes in bile salt metabolism and hepatic transport result in a marked increase in bile flow before postnatal d 17, and thus this study examined the effects of bile salt feeding on the development of ileal bile acid transport. Twelve-d-old rat pups were gavage-fed saline, taurocholate, or mannitol on a daily basis for 3 d. Sodium-dependent bile acid transport was studied by rapid filtration using ileal brush-border membrane vesicles prepared from the various experimental groups. Taurocholate feeding resulted in precocious development of sodium-dependent bile acid transport and induction of sucrase activity. Mannitol feeding, used as a control for the effects of diarrhea-induced stress, resulted in similar sucrase activity, yet sodium-dependent bile acid transport was induced to only half the level observed in taurocholate-fed animals (3.2 +/- 1.6 versus 6.9 +/- 2.0 pmol/mg protein/45 s, p < 0.001). Serum corticosterone levels were similar in the mannitol- and taurocholate-fed animals (3.8 +/- 1.3 versus 4.6 +/- 1.8 micrograms/dL). Both feedings lead to histologic maturation of the ileum, with a more pronounced effect in the taurocholate-fed pups. Bile salt feeding induces precocious expression of ileal bile acid transport, apparently by both diarrhea-induced stress and a bile salt-specific effect.
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PMID:The effects of bile acid feeding on the development of ileal bile acid transport. 846 58

Taurocholate transport was studied in brush border membrane vesicles (BBMV) isolated from chicken small (duodenum, jejunum, and ileum) and large (proximal cecum and rectum) intestines, using a rapid filtration technique. The purity of the BBMV was verified by the finding that the specific activity of sucrase (a brush border membrane enzyme marker) was severalfold greater in vesicles than corresponding values in mucosal homogenate. The functional integrity of isolated BBMV was evaluated by the uptake of D-glucose, which showed a transient increase in the presence of Na+. A Na+-dependence of taurocholate uptake was shown in BBMV prepared from ileum, cecum, and rectum, as taurocholate transport was transiently increased (accumulation) in the presence of a Na+ gradient between the external medium and intravesicular medium. The magnitude of the accumulation was similar among ileum, cecum, and rectum. In contrast, BBMV prepared from duodenum and jejunum did not show any Na+-dependent taurocholate transport, as the taurocholate uptake was not affected when a Na+ gradient was replaced by a K+ gradient. The use of taurochenodeoxycholate in the incubation medium inhibited Na+-dependent taurocholate transport in the ileum, cecum, and rectum. This study is the first to show the presence of a Na+-dependent bile salt transport in BBMV obtained from chicken ileum, proximal cecum, and rectum.
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PMID:Taurocholate transport by brush border membrane vesicles from different regions of chicken intestine. 956 44