Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Microscopical studies showed that initial differentiation of the guinea-pig small intestine occurs between days 35 and 55 of foetal development. Changes observed at this time include formation of villi (by day 42), elaboration of submucosal duodenal Brunner's glands (by day 49) and the appearance of a well-developed microvillus membrane (by day 56). Different microvillus membrane-associated hydrolases appear at different stages of foetal and postnatal development. The 'early' enzymes such as aminopeptidase, alkaline phosphatase and sucrase show a sharp increase and reach their maximal levels between days 35 and 50, whereas the late enzymes such as dipeptidyl peptidase IV and lactase increase gradually between days 35 and 50, and reach maximal activity between days 50 and 60. A combination of techniques involving precipitation with Mg2+ followed by fractionation on sucrose density gradients has enabled us to prepare, for the first time, a 21-fold enriched microvillus membrane fraction from the foetal intestine. Polypeptide analysis of this membrane fraction by sodium dodecyl sulphate/polyacrylamide gel electrophoresis showed the presence of developmentally specific polypeptides at different stages of foetal and postnatal development. Three polypeptides of molecular weights 205 000, 80 000 and 47 000 are major microvillus membrane components at the 40-day foetal stage. Two other polypeptides of molecular weights 60 000 and 131 000 are major microvillar components at 56-day and older foetal stages as well as at the 3-day neonatal stage. The adult microvillus membrane contained 112 000 and 122 000 Mr polypeptides as major components. The above results were confirmed using two-dimensional isoelectric focussing-sodium dodecyl sulphate/polyacrylamide gel electrophoretic techniques.
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PMID:Structural and biochemical differentiation of the mammalian small intestine during foetal development. 653 51

The gastric- and intestinal-type properties of 15 human gastric cancers, which were transplanted into nude mice, were studied biochemically and histologically. Enzyme activities were determined in the crude extracts of cancer tissues: pepsinogen isozymes as gastric marker enzymes; and sucrase, aminopeptidase (microsomal), and alkaline phosphatase as intestinal marker enzymes. By hematoxylin and eosin staining and paradoxical concanavalin A staining, gastric cancer tissues were classified into gastric type (pyloric gland cell type and surface mucous cell type) and intestinal type (goblet cell type and intestinal absorptive cell type). On the basis of their properties, human gastric cancers were classified into four types: (a) intestinal type; (b) gastric type; (c) intestinal plus gastric type; and (d) unclassified type, showing no gastric- or intestinal-type properties. Of six well-differentiated adenocarcinomas, four were of intestinal type, one of gastric type, and one of intestinal plus gastric type. All of the intestinal-type carcinomas showed sucrase activity. Of the three signet ring cell carcinomas, one was classified as a gastric type, one as an intestinal plus gastric type, and one as an unclassified type. Of the six poorly differentiated adenocarcinomas, five were of the intestinal type and one of the unclassified type. The present results clearly showed the appearance of intestinal-type properties in gastric cancer cells not only in so-called intestinal-type carcinomas, but also in diffuse-type carcinomas.
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PMID:Gastric- and intestinal-type properties of human gastric cancers transplanted into nude mice. 669 75

The present study is concerned with a multilevel approach to human colon organogenesis, involving scanning and transmission electron microscopy together with brush border enzymology. The results emphasize the particular developmental pattern of sucrase activity which appears towards 11 weeks, increases at 14 weeks, begins to decrease around 28 weeks and disappears totally at term. In contrast, other enzymes like aminopeptidase and alkaline phosphatase persist in the adult colon. The correlation, in the fetal large bowel, of enzyme activities and villus structures similar to those found in the small intestine is discussed.
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PMID:Developmental pattern of brush border enzymes in the human fetal colon. Correlation with some morphogenetic events. 671 37

Jejunum of 19-day fetal rats was explanted in organ culture for 48 h in the presence of dexamethasone (DX) and cycloheximide (CX) or actinomycin D (Act D). The concentrations of both inhibitors which provided maximal responses without any detrimental alteration of the tissue were determined. During the culture period, CX (0.5 microgram/ml) totally abolished the production of both DX-stimulated enzymes (sucrase, maltase, lactase) and DX-insensitive enzymes (aminopeptidase, alkaline phosphatase). On the contrary, Act D at 2 micrograms/ml exhibited differential levels of inhibition related to the enzyme considered: 100% for sucrase and aminopeptidase, 70% for maltase and 50% for lactase. By contrast, alkaline phosphatase was stimulated 100% by Act D. These data suggest that the mechanism by which DX induces sucrase and stimulates maltase activity takes place at the transcriptional level. They also indicate that the basic maturation of at least maltase and lactase activities depends upon the traduction of a preexisting pool of mRNAs. The superinduced alkaline phosphatase activity obtained with Act D supports the notion that an Act D-sensitive repressor may play a role in the maturation process of this enzyme.
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PMID:Organ culture of fetal rat intestine. Effects on brush border enzyme activities of the combined administration of dexamethasone and cycloheximide or actinomycin D. 672 12

Jejunal mucosa of 6 d-old rats were cultured for 24 and 48 h in the presence of thyroxine, insulin, pentagastrin, glucagon, epidermal growth factor (EGF) or dibutyryl-A-3:5-MP cyclic with or without dexamethasone (DX). The enzymes were assayed on the purified brush borders. The various agents added alone to the basic culture medium had no effect with the exception of DX on the levels of enzyme activities. Dexamethasone alone induced sucrase, stimulated maltase, and protected other brush border enzyme activities (aminopeptidase, lactase, and alkaline phosphatase). When added to DX-supplemented medium, only the following factors modified the levels of enzymatic activities observed with DX alone. Insulin (10(-6) M) increased maltase, alkaline phosphatase, and lactase activity to a greater extent than DX at 24 h culture, the effect being maintained at 48 h on alkaline phosphatase only. At 48 h culture, both EGF (10(-8) M) and dbcAMP (10(-3) M) decreased DX-induced sucrase activity. The latter agent also depressed DX-stimulated aminopeptidase activity.
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PMID:Organ culture of suckling rat intestine: comparative study of various hormones on brush border enzymes. 674 50

We found in rats submitted to a 7 days interval of hypokinesia a decreased glycoprotein content in salivary mucous glands, gastric and intestinal mucosa, an increased glycoprotein content and an increased content of leucine-aminopeptidase, acid and alkaline phosphatase. Similar changes were found after a short interval of centrifugation (+6 Gz, 10 min). These nonspecific responses were more accentuated if the hypergravitation was performed after 7 days of hypokinesia. We reproduced this way this events that occurred in space flight and deacceleration before landing.
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PMID:Digestive tract of rats after hypokinesia and hypergravitation. 678 92

Hypokinesia produced specific reactions in tissues related to motion (bones, skeletal muscles and myocardium) and nonspecific in others, as that of the digestive tract after 7 days of hypokinesia. A decreased content of glycoproteins from mucous salivary glands, stomach, small intestine and colon, and an increased intestinal content of leucine-aminopeptidase and acid and alkaline phosphatase were found as a result of histochemical reactions. An important plasmatic corticosterone increase was also found. The same histochemical modifications appeared in adrenalectomized rats in which the plasma corticosterone was substantially diminished. Therefore these glycoproteins and enzymatic secretions are not dependent on the glucocorticoid response.
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PMID:The digestive tract after 7 days of restraining conditions in normal and adrenalectomized rats. 678 91

The effect of dexamethasone (DX) on the prenatal maturation of rat intestinal brush border enzymes was studied in organ culture. Jejunal segments were explanted daily from day 17 of gestation until birth, as well as at different postnatal stages until day 6; they were cultured for 48 h with or without DX (8 X 10(-8) M). Enzymatic activities were analyzed on brush border membranes purified from cultured intestines and were compared with values from uncultured specimens. The results showed that DX elicited (a) a precocious induction of sucrase activity in the jejunum explanted from 19 days of gestation onward, reaching a peak value when taken at birth; (b) a stimulation of maltase activity in the segments explanted as soon as day 18, leading to maximal values when taken at day 20, the stage at which the stimulated activity reached a 6.5-fold increase over the baseline activity; and (c) an increase of lactase activity comparable to that occurring in utero. As opposed to this, DX has no specific action on alkaline phosphatase and aminopeptidase activities. The present data indicate that glucocorticoids directly and specifically influence the prenatal maturation of some brush border enzymes in the mammalian gut.
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PMID:Control of brush border enzymes by dexamethasone in the fetal rat intestine cultured in vitro. 682 Nov 11

Intestinal metaplasia of the human stomach was classified into two types, complete and incomplete. The complete type was associated with the intestinal marker enzymes sucrose alpha-D-glucohydrolase, alpha, alpha-trehalase, aminopeptidase (microsomal) (APM), and alkaline phosphatase (ALP). Tissue of this type contained goblet cells and Paneth's cells but not high-iron diamine (HID)-positive mucin staining with HID-Alcian blue. The incomplete type of intestinal metaplasia was associated with sucrose alpha-D-glucohydrolase, APM, goblet cells, and HID-positive mucin but not with alpha, alpha-trehalase, ALP, or Paneth's cells. For the examination of the distribution of the complete and incomplete types in 84, 27, and 16 resected specimens of human stomach with gastric carcinoma, gastric ulcer, and duodenal ulcer, respectively, disaccharidases were located with Tes-Tape. Specimens with intestinal metaplasia were divided into three classes: complete type only (class I), incomplete type only (class II), and a mixture of areas of the complete and incomplete types (class III). Of the 84 specimens from patients with gastric carcinoma, intestinal metaplasia was found in 76 (01%), and the percentages of specimens of classes I, II, and III were 32, 22, and 46, respectively. In these specimens, the percent incidence of class I increased and that of class II decreased with age. Of the 27 specimens from patients with gastric ulcer, 16 (59%) shopwed intestinal metaplasia and 10 of the 16 (63%) specimens were of class II. Of the 16 specimens from patients with duodenal ulcer, only 3 (19%) specimens showed intestinal metaplasia and all of them were of class II. The relationships of the complete and incomplete types of intestinal metaplasia to gastric carcinoma wre studied in 26 foci of minute carcinoma of the stomach less than 5 mm in largest diameter. Nineteen of 20 (05%) foci of the intestinal type of minute carcinoma were surrounded by intestinal metaplasia and 16 foci (80%) were surrounded by the incomplete type of intestinal metaplasia.
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PMID:Distribution of marker enzymes and mucin in intestinal metaplasia in human stomach and relation to complete and incomplete types of intestinal metaplasia to minute gastric carcinomas. 693 Dec 45

Urinary high molecular mass proteins (fraction P) solubilized in Triton X-100 and by papain have been compared with the solubilized human renal brush border membrane proteins. Crossed immunoelectrophoresis of Triton X-100 fraction P extract, by means of two polyspecific antisera directed against either renal membrane or fraction P, revealed eleven immunoprecipitates antigenically identical with detergent renal membrane antigens. Among them, five hydrolases were identified by zymogram staining: microvillus aminopeptidase, maltase, trehalase, gamma-glutamyltransferase and alkaline phosphatase. Eight papain-solubilized fraction P proteins and Triton X-100-solubilized membrane extract presented 'identity' patterns in tandem crossed immunoelectrophoresis, but differed in their amphiphilicity, as demonstrated by the change of precipitation pattern on charge-shift caused immunoelectrophoresis. Among the eleven detergent-solubilized fraction P antigens, nine were proved to be amphiphilic proteins and six presented bidirectional charge shifting properties similar to those of renal membrane antigens. Quantitatively, five detergent fraction P proteins were found in the same amounts as in renal membrane extract, two in lesser amounts and four in greater. Moreover, the same two plasma proteins were identified in fraction P as in the renal membrane. Thus important similarities exist between the urinary fraction P and the native renal membrane.
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PMID:Immunochemical analysis of high molecular mass urinary proteins. 712 88


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