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)

Alkaline phosphatase activity has been investigated by histochemical methods in normal and diseased human large intestine. The tissues were constantly maintained at 4 degrees C or below. Specimens were either frozen in liquid nitrogen, freeze-dried and embedded in glycol methacrylate for sectioning at 2 mu, or, fixed in ice-cold formol-calcium for frozen sectioning at 10 mu. The simultaneous coupling azo dye method using the substrates sodium alpha-naphthyl phosphate and Naphthol AS-BI phosphate, resulted in the demonstration of alkaline phosphatase activity in the surface epithelial cells, and the middle and upper crypts, of normal and transitional mucosa.
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PMID:Histochemical demonstration of alkaline phosphatase in human large intestine, normal and diseased. 42 14

Cyanine dye fluorescence and alkaline phosphatase activities have been compared directly by confocal microscopy in a wide variety of cells present in the follicle-associated epithelium of the mouse Peyer's patch to test the hypothesis that antigen-transporting M cells have a low membrane potential. In order to make these comparisons it was first necessary to equilibrate living tissue with the membrane potential sensitive dye DIOC5(3), fix with glutaraldehyde and then incubate the fixed tissue with naphthol AS-BI phosphate, a substrate which is hydrolysed by alkaline phosphatase present in the luminal membrane of these epithelial cells. Naphthol AS-BI produced by this reaction is then coupled to Fast Red TR diazonium salt at the site of hydrolysis. Selecting the 488 nm wavelength of the argon laser source then allows one to measure alkaline phosphatase activities as Fast Red absorbance and membrane potentials by DIOC5(3) fluorescence. Results obtained show a linear correlation between membrane potential and alkaline phosphatase activity. Relative lack of alkaline phosphatase activity, determined in fixed tissue, has been used previously to identify antigen-transporting M cells (Smith et al., 1987). The present work shows that it is now possible to recognize these cells in living tissue by measurement of DIOC5(3) fluorescence. The possible importance of this finding in providing a way to study cell surface-antigen interactions taking place in living tissue is discussed.
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PMID:Confocal microscopical analysis of epithelial cell heterogeneity in mouse Peyer's patches. 160 96

A new technique of quantitative histochemistry has been developed to study the cellular composition of the follicle-associated epithelium of the mouse Peyer's patch. This technique involves applying naphthol AS-BI phosphate to the surface of intact tissue where it is hydrolysed by alkaline phosphatase present in the luminal membrane of the epithelial cells. Naphthol AS-BI produced by this reaction is then coupled to Fast Red TR diazonium salt at the site of hydrolysis. M cells present in the epithelium contain little alkaline phosphatase activity and, therefore, remain white. Treatment with Alcian Blue is finally used to label goblet cells. Subsequent quantitative analysis of alkaline phosphatase-rich cells is carried out by scanning microdensitometry. Using this technique it is possible to detect two populations of alkaline phosphatase-containing cells in mice reared in a normal animal house environment. These results are discussed in relation to possible interactions taking place between enteric antigens and the gut-associated lymphoid tissue which could reduce the ability of follicle-associated enterocytes to express alkaline phosphatase.
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PMID:Automated histochemical analysis of cell populations in the intact follicle-associated epithelium of the mouse Peyer's patch. 319 21