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)

A fast-moving alkaline phosphatase band on polyacrylamide gel electrophoresis has been found in 6 patients with carcinoma of the liver and gastrointestinal tract. This isoenzyme resembled the placental isoenzyme in its inhibition by L-phenylalanine, its resistance to L-homoarginine inhibition and its molecular weight. However, it differed from the placental and Regan isoenzymes in its sensitivity to L-leucine and ethylenediaminetetra-acetic acid, its lower retardation by neuraminidase, its electrophoretic mobility and its decreased heat stability. The latter two properties also distinguished it from the Nagao isoenzyme. It was identified as the Regan Variant. The Regan Variant has hitherto been reported largely in hepatocellular carcinoma. In the presented paper we report its appearance in the sera of patients who have neoplasms in a variety of primary sites in the gastrointestinal tract. It is emphasized that, while the presence of the Regan Variant in serum may be taken as evidence of carcinoma, no conclusions can be drawn as to the site of the disease.
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PMID:Regan variant alkaline phosphatase in gastrointestinal carcinoma. 65 33

In duodenal ulcer alkaline phosphatase activity was the highest in mucosa of pyloric region of curvature ventriculi minor and it decreased distinctly in the tissues removed from pylorus. In cases of gastric ulcer, the enzymatic activity was high throughout the curvatura ventriculi minor reaching the maximal value at the ulcerous zone. Alkaline phosphatase from gastric mucosa resembled the enzyme from intestine in its inhibition patterns with 1-phenylalanine and in inactivation properties at 56 degrees within 15 min; but, as distinct from the latter, the enzyme was more stable at 65 degrees within 5 min, maintaining 50% of the initial activity.
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PMID:[Distribution and properties of the alkaline phosphatase in the human gastric mucosa in peptic ulcer]. 66 46

Brush border membrane vesicles were isolated from rat kidney cortex by differential centrifugation in the presence of 10 mM calcium. Their properties were compared to brush border vesicles isolated by free-flow electrophoresis. By the calcium precipitation method membrane vesicles were obtained in a shorter time with a similar enrichment of brush border marker enzymes (11- to 12-fold for alkaline phosphatase and maltase), with a similarly reduced activity of the marker enzyme for basal-lateral plasma membranes and an almost identical protein composition as revealed by polyacrylamide gel electrophoresis in sodium dodecyl sulfate. The transport properties of the two membrane preparations for D-glucose, L-phenylalanine, and phosphate are essentially the same; there is some indication for a lower sodium permeability of the vesicles prepared by the calcium precipitation method. The latter vesicles were also shown to exhibit sodium gradient stimulated uptake of L-glutamate.
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PMID:Properties of brush border vesicles isolated from rat kidney cortex by calcium precipitation. 75 88

A combined method of phosphatase histochemistry and (3H)thymidine radioautography was devised to study the subcellular localization of alkaline phosphatase (AP) activiity with changing pattern of cell proliferation in precancerous livers of rats fed dimethylaminoazobenzene. After 50 hr of continuous infusion of (3H)thymidine into the rats, labeled liver tissue were fixed in glutaraldehyde. Sections were incubated for AP activity in a lead citrate medium (pH 9.4) with beta-glycerophosphate as substrate. Light and electron microscopic examinations of radioautographs revealed that focal groups of 3H-labeled hepatocytes within hyperplastic nodules were coincident to hyperbasophilic foci and distinguishable from the surrounding parenchyma, which was sparsely labeled. Proliferative hepatocytes in the foci exhibited enzyme reaction product indicative of AP activity along the entire surface membranes. The surface AP tography was in contrast to that of the surrounding hyperplastic parencyma, in which regenerative hepatocytes showed a normal localization of AP activity at the bile canalicular membranes. The L-phenylalanine-sensitive snd heat-resistant activity of hyperbasophilic hepatocytes was different from that of normal hepatocytes. The surface enzyme differentiation was accompanied by a decrease of cytoplasmic AP. Golgi elements apparently function in the mobilization of AP into the surface membranes. The phenomena of AP alterations might be related to the abnormal control of cell proliferation and cytodifferentiation leading to malignant growth.
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PMID:Cell proliferation and subcellular localization of alkaline phosphatase activity in rat liver parenchyma during azo dye carcinogenesis. 80 69

Squamous cell carcinomas were induced in the hamster cheek pouch with 9,10-dimethyl-1,2-benzanthracene. The process of carcinogenesis was inhibited by phenylphosphate, an inducer of alkaline phosphatase. Orthophosphate and l-phenylalanine, which inhibit alkaline phosphatase, had a promoting effect on tumor formation. The results are in accordance with those of previous studies on the effect of inducers of alkaline phosphatase on chemical carcinogenesis. The effect of the studied substances on carcinogenesis was apparently unrelated to the presence of phenyl or phosphate groups or of steroid rings. The tumor inhibition or promotion seemed to be related to the potential of the tested substances to induce or inhibit alkaline phosphatase activity.
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PMID:Chemical carcinogenesis in the hamster cheek pouch. Influence of inhibitors and inducers of alkaline phosphatase. 81 3

1. Alkaline phosphatase (orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1) from human intestine was purified with concanavalin A-Sepharose and tyraminyl derivative-Sepharose affinity chromatography. The enzyme obtained with these techniques had a specific activity of approx. 513.2 mumol p-nitrophenylphosphate hydrolyzed per min per mg of protein at pH 10.0. 2. The highly purified enzyme showed one major enzymatically active band and a possible minor enzymatically active band on acrylamide gel and cellogel electrophoresis, and the two fraction types showed identical antigenicity. 3. The highly purified intestinal enzyme was compared with the purified hepatic enzyme: the saccharide content of each showed a marked difference. 4. The interaction of alkaline phosphatase with concanavalin A, a carbohydrate-binding protein, was studied. Concanavalin A showed an organ-specific behavior to alkaline phosphatase isoenzyme, i.e., the effect on the enzyme activity, and the optimum pH of the activity. 5. The concanavalin A and alkaline phosphatase complex showed a protective effect against heat denaturation and inactivation of proteinase digestion. There was no difference in stability between the intestinal enzyme and the hepatic enzyme. 6. Alkaline phosphatase preparations from human intestine and human liver can bind with concanavalin A; these interactions of concanavalin A; these interactions of concanavalin A with the enzyme occurred reversibly when alpha-methyl-D-mannoside was added. 7. The double reciprocal plots of 1/v vs. 1/s at higher concentrations of concanavalin A showed that the mechanism of inhibition was "mixed type". From the results of Dixon plots, the inhibition constant (Ki) was calculated to the 0.025 muM for human intestinal enzyme. 8. The effect of concanavalin A on L-phenylalanine inhibition of the intestinal alkaline phosphatase indicates that concanavalin A does not interfere with L-phenylalanine binding, but its effect on L-homoarginine inhibition of the hepatic enzyme seems to show that concanavalin A interfered with L-homoarginine binding.
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PMID:Partial purification of human intestinal alkaline phosphatase with affinity chromotography. Some properties and interaction of concanavalin A with alkaline phosphatase. 82 66

L-p-Bromotetramisole is proposed as a new reagent for use in determining intestinal and (or) placental isoenzymes of alkaline phosphatase in human serum. Its main advantage over L-phenylalanine is its high discriminating potency at very low concentrations. For highest accuracy, the samples may even be "titrated" with the inhibitor. Analytical recoveries of intestinal and placental isoenzymes in serum are complete, and results correlate well with those by other methods. At the appropriate concentrations, L-p-bromotetramisole gives nearly identical results on a variety of sera, irrespective of the buffer used. Within-day CV's were 6.1 and 2.1 for 20% and 60% of the resistant isoenzyme activity, respectively. The day-to-day CV was 3.45 for a sample containing 53.3% of the resistant isoenzyme (n=15). The well-known increase in placental isoenzyme activity with time of gestation could be confirmed on 612 sera from pregnant women. The activities of the intestinal isoenzyme in sera from healty blood donors (n = 126) and hospitalized patients (n = 135) agree with previous findings obtained by the other techniques.
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PMID:L-p-Bromotetramisole, a new reagent for use in measuring placental or intestinal isoenzymes of alkaline phosphatase in human serum. 83 32

The dog jejunum is a much denser tissue than the ileum, with a greater weight per unit length and higher proportion of mucosal tissue. Morphometric analysis reveals longer and wider villi, deeper crypts and larger enterocytes in the jejunal mucosa. Uptake of phenylalanine or beta-methyl-glucoside by tissue slices in vitro is slightly greater in jejunal than in ileal tissue. The levels of acid phosphatase and alkaline phosphatase in the individual enterocytes are significantly greater in the jejunum, according to quantitative histochemical analysis. The absorption of water, sodium, potassium, chloride and glucose in vivo is significantly smaller in the jejunal than in ileal loops, particularly when expressed in terms of unit mucosal weight. Sodium and water absorptions are stimulated by glucose at both sites, but the stimulation is significantly greater in the ileum. Opposite results have been obtained in rats where the transport of phenylalannie in vitro is greater in the ileum, but water, electrolyte and glucose absorption in vivo is greater in the jejunum.
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PMID:Functional and structural characteristics of the jejunum and ileum in the dog and the rat. 84 73

Liver, intestinal, and bone alkaline phosphatase isoenzymes were measured using heat stability and L-phenylalanine inhibition techniques in 78 patients on intermittent haemodialysis. Fifty-five patients had abnormalities in one or more of the isoenzymes. Changes in bone and intestinal alkaline phosphatase activities seemed to be related and raised liver isoenzyme activity was associated with the development of liver disease. Abnormal histological and radiological findings were better correlated with bone alkaline phosphatase levels than with total alkaline phosphatase, and serial estimations of bone isoenzyme activity were useful in assessing the response of renal osteodystrophy to treatment with a vitamin D analogue. Serum alkaline phosphatase isoenzyme measurement provides another useful and non-invasive index for monitoring metabolic bone disease in patients with chronic renal failure.
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PMID:Comparative study of alkaline phosphatase isoenzymes, bone histology, and skeletal radiography in dialysis bone disease. 86 92

Rats depleted of magnesium for 13 days were killed after 18 to 20 hours of fasting or 2 hours after consumption of a standard-sized meal. Serum and duodenal alkaline phosphatase (AP) were reduced in fasted magnesium depleted rats compared to pair-fed and ad libitum-fed controls. With refeeding, serum alkaline phosphatase levels rose significantly in all groups, but the levels in refed Mg deficient rats remained below serum levels of fasted control rats. Inhibition of AP activity with L-phenylalanine and urea suggested that the differences in AP levels of fasted and fed rats were mainly due to enzymes of intestinal origin. Intestinal AP levels increased after feeding in all groups, but were proportionately greatest in Mg depleted rats. The pattern of serum and duodenal AP in fed and fasted rats and the results of polyacrylamide disc gel electrophoresis (PADGE) in duodenal AP extracts suggest that Mg depletion alters the release of AP into the blood that normally occurs in response to feeding.
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PMID:Serum and duodenal alkaline phosphatase levels in fed and fasted magnesium deficient rats. 86 16


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