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)

In the present investigation the localization and activity of alkaline, neutral, and acid hydrolases of the thymus were studied during development of rats and mice and of various adult species using histochemical methods. If different procedures of tissue pretreatment were employed, several inhibition effects and morphological as well as enzyme histochemical artifacts occurred dependent on the mode of tissue pretreatment. After embedding in glycol methacrylate, sections of the thymus showed a better structural preservation than cryostat sections but were accompanied by a drastic decrease of activity and low localization quality of the final reaction products especially in the case of protease studies with 4-methoxy-2-naphthylamine peptides as substrates. Smears of thymic cells facilitated the allocation of enzymes to mobile or fixed cells in the stroma of the thymus. The perivascular localization of aminopeptidase M could only be shown with combined techniques. In comparison, primarily the proteases yielded information on the thymic stroma and in this context especially on the epithelial reticular cells and the stroma proper but also on thymocytes (lymphocytes) and enabled a species-dependent subdivision of the thymic reticulum already in the light microscope. Enzyme histochemically the development of the rat and mouse thymus could be subdivided into an early period and perinatal (pre- and postnatal) period of functional differentiation. Morphological (proliferation of cortical lymphocytes) and enzyme histochemical changes (disappearance of dipeptidylpeptidase IV, significant loss of alkaline phosphatase activity and beginning activity increase of aminopeptidase M) occurred primarily at the transition from the early to the prenatal period. During the postnatal phase, a significant activation of lysosomal enzymes in the thymic medulla and general enzymatic differentiation of the cortical epithelial reticular cells were found. Species differences and species similarities for the respective enzymes and their localization as well as for the thymic cells were noticed for adult rats, mice, guinea-pigs, hamsters, and marmoset monkeys. Differences were true especially for the thymocytes; less species differences were seen for the epithelial reticular cells; capsular and perivascular connective tissue and the macrophages behaved rather similarly. Species-independently certain medullary epithelial reticular cells showed high and typically localized alkaline phosphatase activities and species-dependently also high activities of neutral hydrolases.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[Hydrolase histochemistry of the thymus: development and species variations]. 250 44

Studies of T (thymus-derived) lymphocyte ontogeny in the guinea pig have been hampered by the lack of suitable antigenic or other markers for various T cell subpopulations in this species. Monoclonal antibodies that recognize three distinct surface proteins of guinea pig T cells and react with all peripheral T cells have been used in combination with membrane alkaline phosphatase (AP) to characterize stages of guinea pig T cell development and to determine anatomical localization of different T cell subpopulations. Flow cytofluorographic analysis of thymus, spleen, and lymph node lymphocytes was used to characterize monoclonal antibody specificity. Cortical thymocytes in tissue sections expressed membrane AP activity and contained nuclear terminal deoxynucleotidyl transferase; medullary thymocytes reacted strongly with one of the monoclonal antibodies (8BE6), minimally with a second (5CD2), and not at all with a third (11AE3). In contrast, polyclonal rabbit antiguinea pig T cell antiserum reacted with both cortical and medullary thymocytes. Staining of tissue sections of lymph node and spleen revealed AP+ lymphocytes to be present peripheral to the mantle region of lymph node follicles and to be randomly scattered throughout the splenic red pulp. T cells reactive with monoclonal antibodies were located primarily in paracortical regions of lymph node and the central region around the periarteriolar regions of the spleen. Dual staining of frozen sections and cell suspension of guinea pig lymphoid tissues for AP activity and surface proteins unique to T cells showed that AP+ cells lacked T cell markers. Dual staining for AP activity and surface immunoglobulins or esterase activity showed that AP+ cells are not likely to be derived from either B cell or monocyte-macrophage lineages. AP+ cells in guinea pig secondary lymphoid tissue may represent a unique subset of lymphocytes of unknown function.
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PMID:Guinea pig T lymphocyte development analyzed by enzyme histocytochemistry, monoclonal antibodies, and flow cytometry. 257 90

A monoclonal antibody of immunoglobulin class G1 has been produced which reacts with a high molecular weight antigen apparently present exclusively in osteogenic tissues. Immunohistochemical studies have shown that the antigen is present throughout the mineralized matrix and in osteoid. None of the other tissues examined namely liver, intestine, kidney, spleen, thymus, heart, lung, skin, cartilage and skeletal muscle showed evidence of specific antibody binding. Immunohistochemical staining was also demonstrated in tissues developing from rabbit marrow cultured in vitro and in diffusion chambers in vivo. Temporal studies of antigen expression in the chambers indicated that the antigen occurs at sites of bone formation after the appearance of alkaline phosphatase but before the formation of a mineralized matrix. The results of these studies suggest that the monoclonal antibody recognises a product of differentiated osteoblasts. This antibody may therefore prove useful in studies of osteogenic differentiation.
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PMID:Immunohistochemical studies using BRL 12, a monoclonal antibody reacting specifically with osteogenic tissues. 263 Jan 75

We employed an immunocytochemical method to examine human brain for the presence of immunoreactive thymosin alpha 1 (T alpha 1), a peptide derivative of thymic tissue, using a well-characterized antiserum. For cell identification, serial sections were stained with antisera to thymosin beta 4(T beta 4), another thymic peptide that identifies oligodendrocytes, and with anti-glial fibrillary acidic protein (GFAP) antiserum that stains astrocytes in a double-staining technique using avidin-biotinylated horseradish peroxidase or avidin-biotinylated alkaline phosphatase complex. Antiserum to T alpha 1 stained the cell body, but not the processes, of GFAP-positive astrocytes, suggesting that T alpha 1 is a common antigen shared between thymus and astrocytes. Because T alpha 1 and its precursor molecule play a role in cell proliferation and immunomodulation, our findings could explain the role of astrocytes in certain central nervous system diseases.
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PMID:Localization of immunoreactive thymosin alpha 1 in astrocytes of normal human brain. 277 14

Groups of ten C57BL/6CrSlc SPF mice of each sex were fed diets containing 0, 6, 12 or 30 ppm nivalenol for 4 or 12 wk. Body-weight gains of males and females were depressed, dose-dependently in the case of males. Feed consumption was also depressed. Treatment-related changes in liver, kidney, spleen and thymus weights were seen in some groups but showed no clear trends. No gross or histopathological lesions were seen in the organs examined but treated groups had considerably less fatty tissue at autopsy than did controls. There was a dose-dependent increase in serum alkaline phosphatase activity. Other serum parameters showed scattered significantly altered value but no clear trends, except for serum GOT values for males fed 12 and 30 ppm for 12 wk; these showed a statistically significant dose-related increase, but were within the normal range and were not considered to indicate hepatotoxicity.
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PMID:Subchronic feeding studies with nivalenol in C57BL/6 mice. 280 3

Male Wistar rats received a low-protein (4.5% protein) diet during 30 days, and T-2-toxin was administered to them through a gastric tube, in a dose of 0.54 mg/kg, during 15 days. The results obtained showed activation of hepatic lysosomal enzymes (sulfatase A and B aryl and beta-glucosidase) and alkaline phosphatase, and to an essential suppression of enzymatic activity of peroxisomes - catalase, glycolate oxidase and D-amino acid oxidase. A sharp aggravation of the intoxication symptoms and pronounced intensification of changes in enzymatic activity in the liver, spleen, thymus and blood serum were recorded in the animals given T-2 toxin simultaneously with the low-protein diet.
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PMID:[Enzyme parameters in the evaluation of the combined effects of protein deficiency and T-2 mycotoxin]. 289 95

In the thymus of normally fed pregnant rats the plasma membrane enzymes dipeptidyl peptidase IV (DPP IV) and alkaline phosphatase (alP) were found in cortical and medullary lymphocytes (thymocytes). Plasma membrane aminopeptidase A (APA) and adenosine monophosphate hydrolysing phosphatase (AMPP) were present in cortical reticular cells. In medullary reticular cells, aminopeptidase M (APM), gamma-glutamyl transferase (GGT), adenosine triphosphate (ATPP) and thiamine pyrophosphate (TPPP) cleaving phosphatases were detected. Medullary reticular cells did not contain APA. Lysosomal DPP I and II, acid phosphatase, acid beta-D-galactosidase, beta-D-N-acetyl-glucosaminidase, beta-D-glucuronidase and non-specific esterases occurred especially in macrophages at the corticomedullary junction. The 21-day-old fetal thymus showed a similar reaction pattern as the maternal organ except for APA which was absent before birth. After treatment of the pregnant rats with valproic acid (VPA), salicylic acid (SA), streptozotocin (ST) and retinoic acid (RA) APA showed an increase in activity in the thymic cortex. In addition, ST and RA induced AMPP, ATPP and TPPP activity in cortical reticular cells up to the same pattern as in medullary reticular cells. After ethanol (ET) administration severe damages occurred. The thymic cortex was free of DPP IV-positive lymphocytes; the medullary reticular cells showed reduced or no GGT and occasionally an increased APM activity. Dexamethasone (DEXA) given to normal or zinc-deficient rats produced the most severe lesions; thymocytes with DPP IV activity were completely absent in the cortex and medulla. In Zn-deficient pregnant rats similar alterations were observed as after ET.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Enzymatic and morphological response of the thymus to drugs in normal and zinc-deficient pregnant rats and their fetuses. 295 24

We characterized properties of Na+/K+ ATPase and alkaline phosphatase in thymocytes or thymoblasts from mice of two strains: AKR, in which thymoma developed spontaneously and C57Bl, in which the development was induced by X-irradiation (total dose: 5.4 Gy in 3 fractions). We found that before thymoma could be discerned morphologically--properties of the two enzymes altered. There was a decrease in 86Rb uptake and in the rate of ATP hydrolysis per cell (both strains) as well as an increase in alkaline phosphatase activity per cell (C57Bl mice). In both spontaneous and radiation-induced thymomas 86Rb uptake, ATP hydrolysis and 3H-ouabain binding per cell were higher than in normal thymuses. Likewise, alkaline phosphatase activity per cell was higher in thymomas than in thymuses; this increase was accompanied by the appearance of additional isoenzyme(s) (1 in AKR, 2 in C57Bl). These changes were compared with cAMP content and 3H-thymidine incorporation, taken as indicators of the proliferative activity, and their high correlation in both AKR and C57Bl mice allowed to distinguish a pre-leukemic period. In that period thymoblasts clearly differed from the normal ones in Na+/K+ ATPase and alkaline phosphatase properties, as well as proliferation, although the morphology of the thymus was still unchanged.
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PMID:Properties of Na+/K+ ATPase and alkaline phosphatase alter during spontaneous and radiation-induced leukemogenesis in mice. 301 84

The antitumor antibiotic mitomycin C is shown to form a covalent complex with calf thymus DNA under anaerobic conditions in the presence of either NADPH cytochrome c reductase/NADPH, xanthine oxidase/NADH, or the chemical reducing system H2/PtO2. Digestion of the complex with DNase I/snake venom diesterase/alkaline phosphatase yields a single mitomycin deoxyguanosine adduct as the major DNA alkylation product, identified as N2-(2'' beta,7''-diaminomitosen-1'' alpha-yl) 2'-deoxyguanosine (Structure 2). Two minor adducts, 2-5% each of the total adduct pool, are isolated and identified as the 1'' beta stereoisomer of 2 (Structure 3), and 10''-decarbamoyl-2 (Structure 7). The same results were obtained with M13 DNA and poly(dG-dC).poly(dG-dC); however, in the latter case, a minor adduct apparently possessing two deoxyguanosine and one mitomycin unit is isolated. Digestion of the covalent mitomycin-calf thymus DNA complex with nuclease P1 yields four dinucleotide adducts, all of which consist of 2 linked at its 3' end to each of the four possible 5' nucleotides (A, T, G, and C). Upon treatment of each dinucleotide adduct with snake venom diesterase/alkaline phosphatase, 2 is released along with the corresponding free nucleoside. In apparent conflict with the present results, previous reports from another laboratory have indicated that modification of calf thymus DNA by mitomycin C under conditions identical to those described here result in the isolation of three mitomycin C mononucleotide adducts possessing linkages of the drug to N2 and O6 of guanine and N6 of adenine. Evidence is shown suggesting that the latter adducts are actually three of the above four dinucleotide derivatives of 2 obtained independently by us and, thus, all of them in fact possess an identical N2-mitosenylguanine adduct moiety. Model-building studies indicate an excellent fit of the guanine N2-linked drug molecule inside the minor groove of B-DNA with no appreciable distortion of the DNA structure.
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PMID:Reaction of DNA with chemically or enzymatically activated mitomycin C: isolation and structure of the major covalent adduct. 301 44

Three closely related alkaline phosphatase (ALP) genes reside on the long arm of chromosome 2 in man. One of these genes (the placental ALP-1) encodes the classic heat-stable placental alkaline phosphatase. Another gene (the placental ALP-2) is closely related to the placental ALP-1 and may encode the so-called placental ALP-like enzyme of the testis and thymus. The third member of this gene family (the intestinal ALP gene) encodes the intestinal alkaline phosphatase. The expression of the placental ALP-1 and intestinal ALP genes is highly tissue-specific in spite of nearly 90% sequence similarity within their exons. To help determine the basis for this tissue specificity, the nucleotide sequence of the placental ALP-1 gene and some of its 5' flanking region has been determined and analyzed by comparison with placental ALP-2 and intestinal ALP gene sequences. The placental ALP-1 gene transcription unit has 4087 bases between the major cap site and the most distal of several reported 3' ends. The protein coding region is divided by 10 short introns varying in size from 74 to 241 nucleotides. Three of these introns bisect regions of the gene that encode residues conserved between the active site of the Escherichia coli enzyme and the human placental ALP. This result suggests that the human alkaline phosphatase genes have evolved in an intron-independent fashion. A comparison of the placental ALP-1 5' flanking sequence (up to -540) with the analogous sequence of the intestinal ALP gene revealed several deletion/substitutions which could be important in determining the tissue-specific expression of these genes.
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PMID:Nucleotide sequence of the human placental alkaline phosphatase gene. Evolution of the 5' flanking region by deletion/substitution. 304 87


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