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)

Starch gel electrophoresis and inhibition studies with L-phenylalanine, L-homoarginine, L-leucine, L-leucylglycylglycine, and L-phenylalanylglycylglycine were carried out on a series of human alkaline phosphatases [orthophosphoric-monoester phosphohydrolase (alkaline optimum); EC 3.1.3.1] derived from fetal and adult liver, kidney, bone, and intestine. No differences between adult and fetal liver, kidney, or bone alkaline phosphatases were observed by either electrophoretic or inhibition studies. However, the fetal intestinal enzyme could be clearly distinguished from the adult intestinal enzyme by its greater anodal electrophoretic mobility and its retardation after treatment with neuraminidase. Even after extensive neuraminidase treatment, its anodal mobility was still slightly greater than that of adult intestinal alkaline phosphatase. Fetal and adult intestinal enzymes showed the same inhibition profiles with the series of inhibitors both before and after treatment with neuraminidase. A survey of intestinal samples from fetuses and premature infants of various gestational ages indicated that the changeover from the synthesis of fetal to adult intestinal enzyme begins at about 28-32 weeks of gestation. The difference between the fetal and adult forms of intestinal alkaline phosphatase may represent the expression of different gene loci or a difference in post-translational modification.
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PMID:Developmental change in human intestinal alkaline phosphatase. 27 6

Alkaline phosphatases [ALPases; orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1] from dog and human placenta, liver, bone, kidney, and intestine were investigated by inhibition studies with L-homoarginine, L-phenylalanine, and L-phenylalanylglycyl-glycine; by thermostability studies; and by electrophoresis, both before and after treatment with neuraminidase. The inhibitions obtained for each inhibitor with dog placental ALPase closely match those obtained with dog and human liver, bone, and kidney ALPases, but are quite different from those obtained with human placental ALPase. Dog placental ALPase is thermolabile, as are dog and human liver, bone, and kidney ALPases, in marked contrast to human placental ALPase, which is very thermostable. Dog placental ALPase has the same electrophoretic mobility as dog liver, bone, and kidney ALPases after removal of sialic acid residues with neuraminidase. Desialated human placental ALPase differs electrophoretically from desialated human liver, bone, and kidney ALPases, which show the same mobilities. Dog and human intestinal ALPases are distinguished by these various criteria from the liver, bone, kidney, and placental ALPases of both species, but are similar to each other. These results suggest that the ALPase gene locus expressed in dog placenta is not homologous to that expressed in human placenta. Rather, it appears to be homologous to the ALPase locus expressed in dog and human liver and possibly also bone and kidney. Other incomplete data suggest that this may also be true for placental ALPase in other mammalian species. One possible explanation is that human placental ALPase, a relatively recent newcomer on the evolutionary scene, arose from a gene duplication that occurred subsequent to the evolutionary divergence of many other mammalian species.
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PMID:Lack of homology between dog and human placental alkaline phosphatases. 28 36

1. Gel-filtration of an extract from the liver of the local Hausa goat Capra hircus indicated the presence of two molecular forms of alkaline phosphatase (orthophosphoric monoester phosphohydrolase, E.C. 3.1.3.1.). 2. Cellulose acetate electrophoresis showed that the lower-molecular-weight form had a similar electrophoretic mobility to alpha 2-globulin from goat serum, whereas the higher-molecular-weight form had a similar electrophoretic mobility to gamma-globulin. 3. Only the lower-molecular-weight form was detected on electrophoresis of a liver extract which contained some residual n-butanol used in the extraction procedure, whereas dialysed acetone powder obtained from the liver extract contained both molecular-weight forms. 4. The partially purified enzyme showed maximum activity at pH 9.8, and was stimulated by Mg2+. 5. The enzyme was heat-labile, and was competitively inhibited by phosphate ions but uncompetitively inhibited by L-phenylalanine. 6. These results are discussed in terms of the properties of the enzyme from other sources.
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PMID:Some properties of liver alkaline phosphatase from the goat Capra hircus. 31 72

The origin of canine serum alkaline phosphatase (ALP) was investigated by various means. On the basis of electrophoretic migration, neuraminidase treatment, thermal denaturation, and chromatographic fractionation, canine serum was found to contain ALP principally of hepatic origin. There was evidence of only a minor portion of ALP being of osseous origin. Intestinal ALP was not detected in canine serum when monitored by immunochemical technique, L-phenylalanine inhibition, and thermal denaturation.
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PMID:Origin of serum alkaline phosphatase in the dog. 35 72

Sera of several canine patients contained an isoenzyme of alkaline phosphatase (ALP) that resembled intestinal ALP with respect to heat inactivation, L-phenylalanine inhibition, and sensitivity to anti-canine intestinal ALP antibody, but differed with regard to the electrophoretic migration. The electrophoretic mobility of the isoenzyme was slightly cathodal than that of hepatic ALP, and its migration was reduced, similar to that of hepatic isoenzyme after neuraminidase treatment. This isoenzyme, which could be corticosteroid induced, was in the sera of numerous dogs with hepatobiliary disorders and was different from the hepatic isoenzyme that appeared in the sera of dogs with acute hepatitis, based on anti-canine intestinal ALP antibody interaction, heat inactivation, and electrophoretic migration.
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PMID:Diagnostic evaluation of canine serum alkaline phosphatase by immunochemical means and interpretation of results. 35 73

1. The proteins of the intestinal microvillus membrane have been studied during post-natal development in the rat (days 12--37). 2. In suckling animals (up to age 20 days), the majority of alkaline phosphatase, glucoamylase and lactase activities in the distal half of the intestine were located in the supernatant fraction (100000 X g, 60 min). These enzymes were attached to the membrane from the proximal intestine at all ages. 3. Alkaline phosphatase, maltase and lactase activities in the supernatant fractions chromatographed in Sephadex G-200 in positions similar to the corresponding membrane enzyme. Corresponding activities for lysosomal counter-parts of maltase and lactase present in the supernatant fraction chromatographed differently. Moreover, pH optimum of the soluble enzymes was 9.2 for phosphatase and 5.5--6.0 for glycoamylase and lactase. The soluble lactase and alkaline phosphatase were inhibited minimally by p-chloromercuribenzoate, and sodium fluoride respectively. L-Phenylalanine (20 mM) did inhibit the soluble phosphatase by 90%. Thus, the soluble enzymes are not mainly of the lysosomal origin, but have characteristics of membrane-bound enzymes. 4. Polyacrylamide gel electrophoresis in sodium dodecyl sulfate revealed 18 protein bands which were present in adult membranes. Two other proteins were unique for membranes of distal intestine in suckling rats. The proteins corresponding to known enzyme activity changed as expected with age (e.g. sucrase, maltase increased, lactase decreased). Most of the other proteins were also altered in amount during development. Thus, the changes in the microvillus membrane during development in the rat are not limited to specific enzymes.
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PMID:Development of intestinal brush border membrane proteins in the rat. 41 9

The luminal disappearance of unlabeled pyridoxal-5'-phosphate (PLP) was studied in vivo in rat jejunum utilizing a perfused segment model. The PLP was measured by a tyrosine decarboxylase assay. [14C]Dextran was used as a nonabsorbable marker to calculate net water absorption. Initial studies validated the use of [14C]dextran as a nonabsorbable marker and established proper conditions of segment perfusion and sample collection for the measurement of PLP luminal disappearance. Subsequent studies demonstrated significant (67.2%) but incomplete inhibition of PLP disappearance by 80 mM phosphate. When nonperfused PLP in 1.1 mM phosphate buffer or perfused PLP in 80 mM phosphate buffer were incubated in vitro for 15 minutes at 37 degrees in a water bath, only negligible changes in PLP concentration were noted. However, when perfused PLP in 1.1 mM phosphate buffer was similarly incubated in vitro, there was a rapid decay in PLP concentration. L-Phenylalanine (5 mM) significantly inhibited this in vitro decay. Conclusions derived from these studies are: 1) The model used is a valid means of studying in vivo luminal disappearance of PLP in the rat jejunum; 2) a major portion of the disappearance seems to involve hydrolysis by alkaline phosphatase; 3) a significant portion of this hydrolysis occurs intraluminally; and 4) a second mechanism of PLP disappearance, which is nonphosphatase-mediated, also appears operative and may represent absorption of the intact, phosphorylated vitamin.
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PMID:Intestinal absorption of pyridoxal-5'-phosphate: disappearance from perfused segments of rat jejunum in vivo. 44 55

We used the inhibitors bromotetramisole, L-phenylalanine amide, and L-phenylalanine in combination to measure intestinal phosphatase in maternal serum and amniotic fluid. By using high concentrations of these inhibitors, it was possible to measure the three isoenzymes separately. We found no evidence of the presence of meconial alkaline phosphatase in the serum of the mother (six cases) after meconial passage in utero.
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PMID:Use of specific inhibitors to disciminate alkaline phosphatase isoenzymes originating from human liver, placenta and intestine: absence of meconial alkaline phosphatase in maternal serum. 45 43

The screening of a series of 11 metastatic breast tumors for the presence of the placental isoenzyme of alkaline phosphatase (EC3.1.3.1) by RIA revealed one strong producer. The alkaline phosphatase of this tumor was characterized with respect to its immunochemical cross-reactivity, inhibition by L-phenylalanine and levamisole, subunit molecular weight (Mr) and isoelectric point (pl) in two-dimensional electrophoresis, and one-dimensional peptide map. In all parameters of the characterization, the tumor alkaline phosphatase, except for subunit molecular weight which was slightly lower (60,000 versus 64,000 for the placental isoenzyme). No strong placental alkaline phosphatase producers were found among 16 primary tumors examined by RIA. The screening of patients' sera for the placental alkaline phosphatase using RIA indicated elevated levels over post-menopausal controls in 20% of the metastatic patients. Only 3% of the primary patients had elevated serum levels. These results suggest that the placental isoenzyme of alkaline phosphatase may be a useful tumor marker for recurrent breast cancer.
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PMID:Demonstration of placental alkaline phosphatase in human breast cancer. 46 12

1. Self-filling blind loops of jejunum were constructed in three groups of rats; in the first, blind loops were created without further manipulation; in the second the bile was diverted permanently into the lower ileum below the blind loop, whereas in a third neomycin was added to the drinking water throughout the experiment. Two weeks after the creation of the blind loops, they were used for structural and functional studies. 2. Morphometric and microdissection techniques demonstrated that the surface area of the individual villi of the mucosa of 'ordinary' blind loops had increased fourfold in comparison with corresponding control jejunum, whereas the increase was only twofold in rats with bile diversion or in the series treated with neomycin. There were proportional increases in crypt length and mitotoic activity of the crypts in all three series, which suggest that the alterations in the mucosa were due to hyperplasia in both villus and crypt compartments. 3. Sucrase, succinate dehydrogenase, alkaline phosphatase and non-specific esterase activities, determined biochemically or histochemically, were reduced in the mucosae of all blind loops, though the changes were most pronounced in the 'ordinary' blind loops. The accumulation of L-phenylalanine by mucosal slices in vitro was depressed, although the decrease was less marked in the series treated with neomycin. 4. These results suggest that both bacteria and deconjugated bile acids play a role in the development of the hyperplastic changes of the blind-loop mucosa, but that another factor might also be involved: as a possible candidate, stasis of the intestinal contents was considered. 5. To test this hypothesis, loops of rat colon were transposed into the jejunum. Above the transposed loop, the jejunal mucosa developed hyperplasia of both villus and crypt compartments, with a reduction in its ability to accumulate L-phenylalanine. It is argued that these changes, probably caused by stasis of the intestinal contents, are triggered off by the dilatation of the gut, which may also be implicated in the mucosal alterations in blind loops.
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PMID:Structural and functional alterations in the mucosa of self-filling intestinal blind loops in rats. 47 94


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