Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Ca2+-mobilizing action of thrombin was demonstrated in a cell-free platelet membrane system consisting of open sheets of plasma membrane plus sealed membrane vesicles that accumulate Ca2+ and release Ca2+ in response to IP3. Thrombin plus GTP, acting on plasma membrane (not vesicles), produced a soluble factor (destroyed by alkaline phosphatase) that released Ca2+ from the vesicles. This effect of thrombin/GTP was blocked by a monoclonal antibody that binds to vesicles and prevents Ca2+ release by IP3. Pertussis toxin plus NAD ADP-ribosylated plasma membrane polypeptides of 39 and 41 kDa and blocked Ca2+ release by thrombin/GTP, but not by IP3.
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PMID:Stimulus-response coupling in a cell-free platelet membrane system. GTP-dependent release of Ca2+ by thrombin, and inhibition by pertussis toxin and a monoclonal antibody that blocks calcium release by IP3. 310 84

The aim of the present study was to create clearly documented immediate-type allergy to food protein in the intestine of rats and to study some pathophysiological phenomena induced by challenge with the allergen. To achieve this, rats were sensitized with ovalbumin. A passive cutaneous anaphylaxis reaction to ovalbumin was negative in all controls and positive in all test animals when Bordetella pertussis was used as adjuvant. Sixty minutes after an intravenous injection of 125I-human serum albumin and 45 min after an ovalbumin challenge, given by gavage, the rats were sacrificed. The intestine was removed and sections taken for morphologic studies. The remainder was rinsed, opened, cut into measured segments, weighed, and the radioactivity was measured. Disaccharidases, alkaline phosphatase, and protein were estimated in homogenates of epithelium. Results in both control and test animals showed that radioactivity decreased as one moved distally along the intestine. However, radioactivity was significantly higher (p less than 0.01) in the intestine of test animals than in controls. Radioactivity in liver, kidney, spleen, and lungs was identical in test and control animals. There was significant reduction in levels of alkaline phosphatase (p varied from less than 0.05 to less than 0.001), maltase (p less than 0.05), and sucrase (p less than 0.05 to less than 0.01). Lactase activity in contrast was significantly raised (p less than 0.05). There was no change in intestinal morphology or in the intestinal mast cell count.
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PMID:The effect of immediate-type gastrointestinal allergic reactions on brush border enzymes and gut morphology in the rat. 392 23

1. To clarify the nature of the inhibition of whole-cell inwardly rectifying K+ current (IK1) by isoprenaline (Iso) and its antagonism by acetylcholine (ACh), we studied the effects of Iso and ACh and their surrogates on single channel currents (iK1) carried by inwardly rectifying K+ channels in cell-attached and excised inside-out patches obtained from guinea-pig ventricular myocytes. 2. Bath application of Iso suppressed iK1 channel activity in cell-attached patches. This was inhibited by propranolol. Bath-applied forskolin or dibutyryl cAMP mimicked the effect of bath-applied Iso. 3. Exposure of the cytosolic face of inside-out patches to purified catalytic subunit of the cAMP-dependent protein kinase (PKA) also suppressed iK1 channel activity, mimicking the effect of bath-applied Iso on iK1 recorded from cell-attached patches. 4. When applied directly to cell-attached patches via the patch pipette solution, ACh antagonized Iso-induced (1 microM applied via the bath) suppression of iK1 channels. In contrast, bath-applied ACh (10 microM) partially antagonized the effect of low concentrations of Iso (e.g. < 50 nM) on iK1 channels in cell-attached patches but had no detectable effect when 1 microM or more Iso was used. 5. In myocytes pretreated with pertussis toxin (PTX), ACh failed to antagonize Iso-induced suppression of iK1 channels. When inside-out patches were used, bath-applied preactivated exogenous inhibitory G protein subunit, G1 alpha, antagonized the suppression of iK1 channels induced by bath-applied catalytic subunit of PKA (PKA-CS), suggesting that a PTX-sensitive G1 alpha mediates ACh-induced antagonism of Iso-induced suppression of iK1. 6. Neither GTP gamma S nor G1 alpha antagonized the suppression of iK1 produced by bath-applied PKA-CS in inside-out patches when okadaic acid was present in the bath. In addition, bath application of alkaline phosphatase also reactivated iK1 channels suppressed by PKA-CS. 7. Findings in guinea-pig ventricular myocytes suggest that iK1 can be suppressed by a PKA-mediated phosphorylation of the iK1 channel occurring in response to Iso-induced beta-adrenergic receptor activation and that ACh can antagonize the suppression by mechanisms that involve both intracellular and membrane-delimited pathways. The membrane-delimited pathway appears to involve M2-cholinergic receptors, their associated G protein, G1, and a protein phosphatase, all located in the sarcolemma in close proximity to the involved iK1 channels.
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PMID:Beta-adrenergic and cholinergic modulation of inward rectifier K+ channel function and phosphorylation in guinea-pig ventricle. 747 27

Short-term treatment of rat submandibular tissues with 10 microM isoproterenol (IPR) resulted in reduction of mucin secretion in response to the agonist during further incubation, and in increases in EC50 values. This IPR-induced reduction of secretion was coupled with selective decreases in the number of beta-adrenoceptors in the tissues and in their affinity for agonists, as assessed by measurement of the specific binding of [3H]dihydroalprenolol. Treatment of the tissues with IPR caused a 30% decrease in IPR-stimulated adenylate cyclase activity and a 25% increase in the GTP binding capacity of inhibitory G proteins (Gi proteins). This IPR treatment triggered a 60% increase in the ability of pertussis toxin (IAP) to catalyze ADP-ribosylation of Gi proteins in the tissue membranes. Enhanced function of stimulatory G proteins (Gs proteins) was observed only during the first incubation of the tissues with IPR. The IAP-catalyzed ADP-ribosylation of Gi proteins in tissues treated with IPR was decreased by prior treatment with cyclic AMP dependent protein kinase, but was increased markedly by prior treatment with alkaline phosphatase. Neither IPR-induced desensitization of protein secretion nor increase in the IAP-catalyzed ADP-ribosylation of Gi proteins was observed in the tissues pretreated with 0.25 microM okadaic acid. These findings suggest that the regulation of Gi protein phosphorylation plays an important role in the IPR-induced heterologous desensitization of mucin secretion from rat submandibular glands.
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PMID:Mechanism of isoproterenol-induced heterologous desensitization of mucin secretion from rat submandibular glands. Regulation of phosphorylation of Gi proteins controls the cell response to the subsequent stimulation. 769 46

The DNA sequence of a cluster of pKM101 conjugal transfer genes was determined and aligned with the genetic map of the plasmid. Eighteen genes were identified, at least eight and probably 11 of which are required for efficient conjugation. These tra genes are homologous to and colinear with genes found in the virB operon of Agrobacterium tumefaciens Ti plasmids. Seven pKM101 tra genes are also homologous to ptl genes of Bordetella pertussis, which direct the export of pertussis toxin. We used TnphoA to construct translational fusions between pKM101 genes and the Escherichia coli phoA gene, which encodes alkaline phosphatase, and provide evidence that at least 11 of the 18 genes are either fully or partially exported from the cytoplasm.
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PMID:Common ancestry between IncN conjugal transfer genes and macromolecular export systems of plant and animal pathogens. 789 54

Phorbol esters (PDBu) stimulate alpha-secretase cleavage and secretion of the Alzheimer amyloid precursor protein (APP). To determine whether any cytoplasmic residues or sequence motifs mediate the PDBu effect on APP processing, this region of APP was altered by point mutations or deletions. To differentiate the mutated APP from the endogenous APP, the APP751 ectodomain between amino acids 1 and 647 was replaced by a human secreted alkaline phosphatase derivative (SEAP). The resultant fusion protein (SEAP-APP751) was cleaved by alpha-secretase at the same site as full-length APP, and its secretion was stimulated by PDBu at a level similar to APP751. However, PDBu-stimulated secretion of the SEAP-APP751 fusion protein reached its maximum level after 30 min of treatment, while secretion of APP751 reached its maximum after 60 min, suggesting that the APP ectodomain affects the kinetics of APP secretion. Mutation of the cytoplasmic serines to alanines had no effect on the PDBu-stimulated secretion of the SEAP-APP, indicating that protein kinase C (PKC) phosphorylation of the cytoplasmic domain of APP is not important for stimulation of APP secretion. Similarly, deletion of the cytoplasmic domain between amino acids 719 and 751 had no effect on the PDBu-stimulated secretion. However, deletion of amino acids 707-751 resulted in a significant increase in the secretory cleavage of the SEAP-APP707 delta C construct, suggesting that the sequence 707-719 is important for the regulated secretion of APP. Cholera toxin, but not pertussis toxin, reduced the PDBu-induced secretion of APP by more than two-fold, suggesting that the PDBu response may be modulated by a cholera toxin sensitive heterotrimeric G-protein.
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PMID:Study of the phorbol ester effect on Alzheimer amyloid precursor processing: sequence requirements and involvement of a cholera toxin sensitive protein. 805 94

We examined the effect of thrombin on phosphatidylcholine-hydrolyzing phospholipase D activity in osteoblast-like MC3T3-E1 cells. Thrombin stimulated the formation of choline dose dependently in the range between 0.01 and 1 U/ml, but not the phosphocholine formation. Diisopropylfluorophosphate (DFP)- inactivated thrombin had little effect on the choline formation. The combined effects of thrombin and 12-O-tetradecanoylphorbol-13-acetate, a protein kinase C-activating phorbol ester, on the choline formation were additive. Staurosporine, an inhibitor of protein kinases, had little effect on the thrombin-induced formation of choline. Combined addition of thrombin and NaF, an activator of heterotrimeric GTP-binding protein, did not stimulate the formation of choline further. Pertussis toxin had little effect on the thrombin-induced formation of choline. Thrombin stimulated Ca2+ influx from extracellular space time and dose dependently. The depletion of extracellular Ca2+ by EGTA exclusively reduced the thrombin-induced choline formation. Thrombin had only a slight effect on phosphoinositide-hydrolyzing phospholipase C activity. Thrombin induced diacylglycerol formation and DNA synthesis, and increased the number of MC3T3-E1 cells, but DFP-inactivated thrombin did not. Thrombin suppressed both basal and fetal calf serum-induced alkaline phosphatase activity in these cells. Propranolol, an inhibitor of phosphatidic acid phosphohydrolase, inhibited both the thrombin-induced diacylglycerol formation and DNA synthesis. These results suggest that thrombin stimulates phosphatidylcholine-hydrolyzing phospholipase D due to self-induced Ca2+ influx independently of protein kinase C activation in osteoblast-like cells and that its proliferative effect depends on phospholipase D activation.
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PMID:Thrombin induces proliferation of osteoblast-like cells through phosphatidylcholine hydrolysis. 864 17

Treatment of rat parotid tissues with 1 microM isoproterenol (IPR) for 10 min caused a 60% decrease in pertussis toxin (IAP)-catalyzed ADP-ribosylation of Gi alpha and resulted in supersensitivity of amylase secretion from the tissues. However, conversely, IPR treatment for 30 min caused a 40% increase in IAP-catalyzed ADP-ribosylation of Gi alpha, coupled with desensitization of amylase secretion. No changes in Gs function were observed in IPR-induced phenomena. Pretreatment with okadaic acid induced enhancement of the supersensitivity of amylase secretion and disappearance of the desensitization. These phenomena were accompanied with decreases in IAP-catalyzed ADP-ribosylation of Gi alpha. IPR treatment for 30 min caused a 50% decrease in phosphorylation of Gi2 alpha immunoprecipitated with anti-G protein antiserum (AS/7) from [32P]Pi-labeled cells, but such treatment for 10 min caused a 40% increase in phosphorylation in the cells pretreated with okadaic acid. Phosphorylation and dephosphorylation of immunoprecipitates with AS/7 by protein kinase A (PKA) and alkaline phosphatase caused decreases and increases in IAP-catalyzed ADP-ribosylation, respectively, indicating the presence of PKA-mediated phosphorylation sites on Gi2 alpha. Thus, the control of the phosphorylation of Gi2 alpha is of importance and relevance in the regulation of biological processes and cellular responses.
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PMID:Regulation of phosphorylation of Gi2 alpha protein controls the secretory response to isoproterenol in rat parotid tissues. 878 62

Bordetella pertussis produces extracytoplasmic adenylate cyclase toxin (AC) which has received considerable attention as a potential vaccine candidate. Great interest from laboratories involved in production, purification and quality control of acellular pertussis vaccine is focused on finding an appropriate technique for rapid and accurate quantitation of AC antigen. In this paper a competitive ELISA is proposed. A polystyrene microplate coated with purified AC was incubated with the sample to be tested plus anti-AC serum. The bound anti-AC antibodies were measured by sequential reaction with alkaline phosphatase-labelled anti-mouse IgG and p-nitrophenylphosphate. This method showed high specificity, with the 50% inhibition corresponding to 4 micrograms/ml of AC. It also proved to be useful to assess the presence of AC in culture supernatants, with high reproducibility.
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PMID:Quantitation of adenylate cyclase of Bordetella pertussis by enzyme linked immunosorbent assay. 882 56

1. This study was planned to clarify the mechanism of Ca2+ channel facilitation by depolarizing prepulses given to voltage-clamped bovine chromaffin cells. The hypothesis for an autocrine modulation of such channels was tested by studying the effects of a soluble vesicle lysate (SVL) on whole-cell Ba2+ currents (IBa). 2. SVL was prepared from a bovine adrenal medullary homogenate. The ATP content in this concentrated SVL amounted to 3.18 +/- 0.12 mM (n = 4). The concentration of noradrenaline and adrenaline present in the SVL was 11.2 +/- 0.97 and 15.2 +/- 2 mM, respectively (n = 5). A 1:1000 dilution of SVL in the external solution halved the magnitude of IBa and produced a 7-fold slowing of its activation kinetics. The blocking effects of SVL were concentration dependent and quickly reversed upon washout. 3. Inhibition and slowing of the kinetics of IBa by SVL could be partially reversed by strong depolarizing prepulses (+90 mV, 45 ms). This reversal of inhibition, called Ca2+ channel facilitation, persisted in the presence of 3 microM nifedipine. 4. Intracellular dialysis of GDP-beta-S (0.5 mM) or pretreatment of the cells with pertussis toxin (100 ng ml-1 for 18-24 h) prevented the reduction in peak current caused by a 1:100 dilution of SVL; no prepulse facilitation could be observed under these conditions. 5. The receptor blockers naloxone (10 microM) or suramin (100 microM) and PPADS (100 microM) largely antagonized the effects of SVL. Treatment of SVL with alkaline phosphatase or dialysis against a saline buffer to remove low molecular mass materials (< 10 kDa) considerably reduced the activity of SVL. 6. Stopping the flow of the external solution (10 mM Ba2+) gradually reduced the size, and slowed down the activation phase, of the current. Prepulse facilitation of IBa was absent or weak in a superfused cell, but was massive upon flow-stop conditions in the presence or absence of 3 microM nifedipine. 7. Our experiments suggest that facilitation by prepulses of whole-cell current through Ca2+ channels is due to the suppression of an autoinhibitory autocrine loop present in bovine chromaffin cells. By acting at least on purinergic and opiate receptors, the exocytotic release of ATP and opiates will cause a tonic inhibition of the current through a G-protein-mediated mechanism. Such a mechanism will be removed by strong depolarizing prepulses, and will involve preferentially non-L-type channels. In the light of these and other recent results, previously held views on the selective recruitment by prepulses of dihydropyridine-sensitive Ca2+ channels are not tenable.
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PMID:The mechanism of calcium channel facilitation in bovine chromaffin cells. 886 66


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