Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0847097 (acidity)
 15,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of salmefamol, a new beta 2-agonist, on pentagastrin-induced gastric acid secretion was studied in conscious gastric fistula dogs. Salmefamol inhibited the acid secretion, an effect which was dose dependent. The volume as well as the acidity was inhibited. Salmefamol caused an increase in the pulse rate. Propranolol prevented the inhibition of acid output as well as the increase in pulse rate. Practolol, a beta 1-adrenoceptor blocker, had no effect on the inhibition of acid secretion but prevented the increase in pulse rate. Dose-response experiments with 6 doses of pentagastrin and 1 dose of salmefamol showed a decrease in calculated maximal response (CMR) and an unchanged D50. It is concluded that salmefamol strongly inhibits pentagastrin-induced acid output in the dog, and the inhibition follows a non-competitive kinetic. The mechanism of gastric secretion probably involves a beta 2-receptor.
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PMID:Inhibition of gastric acid secretion in dogs by a new sympathomimetic drug. 58 29

We have previously described the structures of neutral and sialylated O-glycosidic mannose-linked tetrasaccharides and keratan sulphate polysaccharide chains in the chondroitin sulphate proteoglycan of brain. The present paper provides information on a series of related sialylated and/or sulphated tri- to penta-saccharides released by alkaline-borohydride treatment of the proteoglycan glycopeptides. The oligosaccharides were fractionated by ion-exchange chromatography and gel filtration, and their structural properties were studied by methylation analysis and fast-atom-bombardment mass spectrometry. Five fractions containing [35S]sulphate-labelled oligosaccharides were obtained by ion-exchange chromatography, each of which was eluted from Sephadex G-50 as two well-separated peaks. The apparent Mr values of both the large- and small-molecular-size fractions increased with increasing acidity (and sulphate labelling) of the oligosaccharides. The larger-molecular-size fractions contained short mannose-linked keratan sulphate chains of Mr 3000-4500, together with some asparagine-linked oligosaccharides. The smaller tri- to penta-saccharides, of Mr 800-1400, appear to have a common GlcNac(beta 1-3)Manol core, and to contain one to two residues of sialic acid and/or sulphate.
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PMID:Structural studies on sialylated and sulphated O-glycosidic mannose-linked oligosaccharides in the chondroitin sulphate proteoglycan of brain. 366 49

The purpose of this study was to elucidate the effect of a beta 1-adrenoceptor agonist on gastric acid secretion in conscious dogs with gastric fistula. Isoprenaline, a beta 1- and beta 2-agonist was used alone and in conjunction with selective blockade of beta 2- and beta 1-receptors. Isoprenaline dose-dependently inhibited the secretory volume and the acidity. The antisecretory effect of isoprenaline was significantly blocked by the beta 1-adrenoceptor blocker practolol and by the beta 1 + beta 2-adrenoceptor blocker propranolol but not by H 35/25, a beta 2-adrenoceptor blocker. This indicates that isoprenaline acts on the acid secretion exclusively through beta 1-receptors. Dose-response experiments with five logarithmically increased doses of pentagastrin and one dose of isoprenaline showed unchanged calculated maximum response and an increase in half-maximum acid response. It is concluded that the inhibitory effect of isoprenaline on gastric acid secretion is of competitive or uncompetitive type.
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PMID:Effect of isoprenaline on pentagastrin-stimulated gastric acid secretion in dogs with gastric fistula. 611 62

Anhydrotetracycline (AHTC), one of the major toxic decomposition products of the antibiotic tetracycline, contains several potential binding sites to metal ions. The acidity constants of the ligand were calculated in aqueous medium (I = 0.1 M) at 25 and 37 degrees C. We found pKa1 = 3.23 +/- 0.08, pKa2 = 5.94 +/- 0.09, and pKa3 = 8.48 +/- 0.02 at 25 degrees C and pKa1 = 3.12 +/- 0.09, pKa2 = 5.86 +/- 0.03, and pKa3 = 8.38 +/- 0.04 at 37 degrees C. The coordination of AHTC to Cu(II) and Ni(II) ions was studied in the solid state as well as in buffered aqueous solution at pH 10.0. At this pH, the formation of the two CuL2 and CuL species was indicated (log beta 1 = 8.41 +/- 0.04 and log beta 2 = 12.55 +/- 0.05), but only the formation of the NiL complex (log beta = 5.74 +/- 0.04) was identified. Spectroscopic data confirm the previous assignment of the C11 and C12 oxygens as the coordination sites, yielding six-membered ring chelates and excluding complexation through any of the potential binding positions on ring A.
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PMID:Metal complexes of anhydrotetracycline. 1. A spectrometric study of the Cu(II) and Ni(II) complexes. 820 70

This study was performed to define the biologically active growth modulators in human gastric juice. Mitogenic activity was evaluated by the incorporation of [3H]thymidine into 3T3 fibroblasts. A negative correlation was observed between pH and mitogenic activity in gastric juice (r = -0.45, P < 0.01). The concentrations of epidermal growth factor (EGF), transforming growth factor-alpha and -beta 1 (TGF-alpha and -beta 1), platelet-derived growth factor (PDGF), and basic fibroblast growth factor (bFGF) in gastric juice did not explain these changes in mitogenic activity. Gel filtration identified growth-stimulating activity due to small molecule mitogens (less than 13 kDa), and growth inhibitory activity only in neutral samples due to a macromolecular substance (larger than 240 kDa) susceptible to trypsin digestion and heat and acid treatments. We conclude that acidity-dependent changes in mitogenic activity observed in this study are due to appearance of acid-unstable, high-molecular-weight, growth-inhibitory substance.
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PMID:Mitogenic properties of human gastric juice. 928 44