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 intestinal dipeptidase and disaccharidase activities were investigated in 120 male albino rats of the Wistar strain after administration of 21 mumol.kg-1 body weight phosalone, 14.8 mumol.kg-1 body weight lindane and 10.5 mumol.kg-1 body weight phosalone combined with 7.4 mumol.kg-1 body weight lindane. The dipeptidase activity under the effect of these comparatively low doses of pesticides reveals slightly to moderate changes. The activity of intestinal disaccharidases after a 90-day phosalone and lindane treatment is markedly decreased, particularly that of sucrase. The mechanism of these changes remains unknown.
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PMID:Effect of the pesticides phosalone and lindane on the activity of some dipeptidases and disaccharidases in rat intestinal mucosa. 9 5

A considerable increase occurs in D-glucose uptake and brush border sucrase and lactase activities in the intestine of monkeys treated with a single oral dose of DDT. Brush border alkaline phosphatase activity remains unaffected in the pesticide treated animals. In vitro addiction of DDT has no effect on the sugar absorption and disaccharidase activities.
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PMID:Effects of DDT (chlorophenotane) administration on glucose uptake and brush border enzymes in monkey intestine. 9 80

Extracellular caseinolytic activity was found in the culture fluid of Streptococcus sanguis ATCC 10556 grown in a dialyzed culture medium. This activity was due to multiple proteases that differed in their elution from hydroxyapatite, sensitivity to enzyme inhibitors, specificity and optimum pH. IgA protease, which splits human immunoglobulin A1 into intact Fc and Fab could be effectively separated from these relatively non-specific proteases and purified to apparent homogeneity in 20% yield by a five-step procedure. Although the bulk of the dextran sucrase activity was separated from the IgA protease, a small amount of sucrase activity remained with the final IgA protease preparation. In polyacrylamide gel electrophoresis at pH 9.5 both activities were located in the single protein band detected in this preparation. A quantitative method for the assay of IgA protease was developed, based on radial immunodiffusion to quantitate the Fab produced. This was used to follow the specific activity and yield during purification, and to characterize some of the catalytic properties of the enzyme. At an enzyme/substrate ratio of 1: 400 (w/w) the protease could effect 50% proteolysis of IgA in overnight incubation at 37 degrees C. The optimum activity was at pH 8.0, and 50% inhibition was achieved at 4 . 10(-4) M o-phenanthroline or 8 . 10(-4) M ethylene diamine tetraacetate. Concentrations of diisopropyl phosphofluoridate, phenylmethyl-sulfonyl fluoride, iodoacetate and p-chloromercuribenzoate up to 10(-2) M were without effect on the IgA protease activity. Full reactivation of the chelator inhibited enzyme could be achieved by the addition of Mg2+, Mn2+ or Ca2+.
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PMID:Studies on extracellular proteases of Streptococcus sanguis. Purification and characterization of a human IgA1 specific protease. 10 57

A sensitive protein-binding assay has been used to measure plasma concentrations of total corticosterone during postnatal development in the rat. These concentrations were extremely low on days 6--12, showed a significant rise by day 14, and then continued to rise until peaking on day 24. Plasma titers of corticosteroid-binding globulin rose even more dramatically from day 12 onward. Consequently, the percentage of total plasma corticosterone, which was protein-bound, showed a gradual rise from 78% on day 12 to 98% on day 24. Despite this trend, when concentrations of free corticosterone were calculated, they were found to have a developmental profile very similar to that of total corticosterone. Assay of jejunal lactase and sucrase in the same animals that were used for the corticosterone studies showed that the ontogenic rise of both total and free corticosterone preceded the developmental changes in the activities of these enzymes by approximately 2 days. The data suggest that the rise in free corticosterone that begins on day 14 acts as a cue for enzymic changes in both liver and intestine.
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PMID:Plasma concentrations of total and free corticosterone during development in the rat. 10 38

Starvation overnight and starvation for 48 h reduced the weight and the protein content of mucosal scrapings, but only minimally reduced the DNA content of the mucosal scrapings. The activity of sucrase and maltase was reduced by both periods of starvation. The activity of lactase and of acid and alkaline phosphatase, however, was less subject to starvation. There were striking differences in the response to starvation between the proximal, mid and distal third of the small intestine. The importance of the proper reference system was discussed.
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PMID:Effect of starvation on small intestinal enzyme activity in germ-free rats. 10 66

Intestinal mucosa from 40 patients obtained by fiber-endoscopic biopsy was assayed for disaccharidases to determine suitability of this tissue for assay. The combined specimens from each patient provided 4.7-38.7 mg of tissue, adequate in all instances for duplicate determinations of protein, lactase, sucrase, and maltase. Tissue remained for assays of palatinase in 39 instances, trehalase and cellobiase in 37, and alkaline phosphatase in 22 cases. Twenty-four subjects had normal lactose tolerance tests and normal sucrase/lactase ratios. Thirteen patients with abnormal oral lactose tolerance tests were identified as having a primary low lactase activity on the basis of elevated sucrase/lactase ratios. This ratio was most helpful in making the diagnosis of a primary low lactase, since the mucosal specimens were not obtained from comparable areas. Tissue from three subjects with an abnormally low maltase was unsuitable for diagnosis. Endoscopic biopsy of mucosa appears to be satisfactory for disaccharidase assays in most instances.
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PMID:Adequacy of endoscopic biopsy specimens for disaccharidase assays. 10 20

General evidence of malnutrition such as loss in body weight associated with intestinal parasitism has been attributed to decreased food intake, to intestinal malabsorption, and to change in host basal metabolism. To establish the relative importance of these factors in this regard, rats with trichinosis were studied. The weights of infected and uninfected animals were followed after being placed on one of three feeding regimens for 1 week--stock diet ad libitum, intraduodenal nutrition, and intravenous nutrition. Infected rats on a stock diet lost weight whereas those on the other two regimens maintained the same weight pattern as uninfected counterparts. The maintainance of body weight occurred despite alterations at the level of the intestinal brush border as indicated by a depression of intestinal disaccharidase activities (sucrase and lactase) and by reduction of monosaccharide absorption (measured as accumulation of beta-methyl glucoside) in the proximal, heavily infected region of the small intestine. There was no compensatory increase in enzyme activity nor in the absorptive capacity in the distal gut. Results support the conclusion that inadequate oral food intake rather than changes in basal metabolism or intestinal pathophysiology accounts for weight loss during the intestinal phase of infection.
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PMID:Enteral and parenteral feeding to evaluate malabsorption in intestinal parasitism. 11 Jan 62

72 h after ligation or external fistulation of the common duct the activities of maltase, sucrase and lactase in the homogenate of the small intestinal mucosa of the rat were determined. The experiments were performed in connexion with intestinal perfusion studies, and the disaccharidase activities were measured in unperfused intestinal segments as well as in intestinal loops which had previously been perfused with a sucrose-containing solution. After bile duct ligation, the sucrase and maltase activities in a previously perfused intestinal loop were not different from those in sham-operated animals, the lactase activity was diminished. In a nonperfused segment, the sucrase activity was greater, the maltase activity was unchanged, and the lactase activity was lower than in control animals. After bile duct fistulation, the sucrase, maltase and lactase activities in a perfused segment were lower than in sham-operated rats. In a nonperfused loop, the sucrase activity was greater, the maltase activity was unchanged, and the lactase activity was lower then in the corresponding control group. These data suggest that bile is a factor which influences the total mucosal disaccharidase activities, and, probably, the intracellular enzyme distribution.
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PMID:Ligation or external fistulation of the common bile duct in the rat. II. Intestinal disaccharidase activities. 11 Jun 39

This study was undertaken to investigate the effect of alcohol on the activity of jejunal disaccharidases (DS). The activity of DS in a preparation of purified brush border membrane of hamster jejunum was measured in the absence and in the presence (0.8 to 6.4% wt/vol) of ethanol. To compare the effect of alcohol on DS with its action on a brush border enzyme of a different group, we also measured the activity of alkaline phosphatase (AP) under similar conditions. Ethanol depressed the activity of sucrase, maltase, and lactase in a dose-dependent and time-dependent manner, but it stimulated the activity of AP. The ethanol-induced inhibition of DS was completely reversible. Kinetic studies indicate that ethanol depressed the Vmax and increased the Km of sucrase and lactase. The Vmax of maltase also decreased, but the Km of this hydrolase was not affected by ethanol. From the results of this study it would appear that acute exposure of the jejunal brush border to ethanol depresses the DS activity of the membrane and that (because the AP was not depressed) the ethanol-induced inhibition of DS is not the result of a general inhibition of all enzymes of the brush border.
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PMID:Effect of ethanol on disaccharidases of hamster jejunal brush border membrane. 11 61

Jejunal and ileal segments from preterm rat fetuses were implanted under the kidney capsula of adult rats. Sucrase, lactase and acid beta-galactosidase activities were determined in the isografts at different times after implantation, and in corresponding segments developing in situ. Whereas fetal intestine contains considerable activity of acid beta-galactosidase and lactase, no sucrase activity is detectable. Similarly -- as in situ -- 4 weeks after the implantation the jejunal segment exhibited higher activity of sucrase and lactase than the ileal segment. Acid beta-galactosidase was more active in ileal than in jejunal segments -- both growing in situ as well as isografts. Experiments have thus demonstrated that the expression of the jejunoileal gradient of activity of the 3 enzymes studied does not depend on direct contact with food or gastric, pancreatic and biliary juices. This gives validity to the suggestion that the gradient may already be programmed in fetal intestinal tissue, but other factors active in situ might be responsible for its magnitude.
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PMID:Development of jejunoileal differences of activity of lactase, sucrase and acid beta-galactosidase in isografts of fetal rat intestine. 11 41


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