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)

Pharmacological studies of glutamate receptor stimulation of the phosphoinositide (PI) system have demonstrated that this response is blocked by several agents: 2-amino-3-phosphonopropionate (AP3), phorbol esters and in some preparations pertussis toxin. In electrophysiological studies of CA1 pyramidal neurons, we have found that pertussis toxin and AP3 (1-2 mM) do not block either the membrane depolarization or inhibition of the slow afterhyperpolarization elicited by trans-1-aminocyclopentyl-1,3-dicarboxylate (ACPD; 30 microM), a selective agonist of the PI-linked glutamate receptor. However, phorbol 12,13-diacetate (1-1.5 microM) which itself blocks the slow afterhyperpolarization, completely blocks the membrane depolarizing response elicited by ACPD. These results add to growing evidence for heterogeneity among PI-linked glutamate receptor responses.
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PMID:Pharmacological characterization of phosphoinositide-linked glutamate receptor excitation of hippocampal neurons. 196 52

The role of protein kinase C in regulating Ca2+ channel activity was investigated using the whole-cell patch-clamp technique in the mouse pituitary tumor cell line AtT-20. The Ca2+ current was activated by depolarizing voltage steps from a holding potential of -80 mV. Extracellular application of the protein kinase C activator 1-oleoyl-2-acetylglycerol (OAG) reduced voltage-dependent Ca2+ current. This effect was reversible and dose dependent (10-100 microM). Pertussis toxin did not block the effect of OAG on Ca2+ current, suggesting that OAG does not affect Ca2+ channels via a pertussis toxin sensitive guanosine triphosphate binding protein. Na+-free solutions did not block the effect of OAG on Ca2+ channels, suggesting that this effect of OAG does not involve the Na+/H+ antiporter. The phorbol esters 12-deoxyphorbol-13-isobutyrate (10 microM) and phorbol-12,13-diacetate (100 microM) also reduced Ca2+ current. The results suggest that protein kinase C may be an inhibitory regulator of voltage-dependent Ca2+ channels.
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PMID:The protein kinase C activator 1-oleoyl-2-acetylglycerol inhibits voltage-dependent Ca2+ current in the pituitary cell line AtT-20. 244 24

Adenylate cyclase (ATP-pyrophosphate lyase (cyclizing); EC 4.6.1.1) in the human keratinocyte cell line SCC 12F was potentiated by 12-O-tetradecanoyl-phorbol-13-acetate (TPA), phorbol-12,13-diacetate, and 1,2-dioctanoylglycerol. Keratinocytes exposed to TPA showed a 2-fold enhancement of adenylate cyclase activity when assayed in the presence of isoproterenol or GTP. The half-maximal effective concentration (EC50) for both isoproterenol and GTP were unaltered by TPA treatment of the cells. Basal adenylate cyclase activity in membranes from TPA-treated cultures was also increased 2-fold relative to activity in control membranes. Potentiation of adenylate cyclase activity was dependent on the concentration of TPA to which the keratinocytes were exposed (EC50 for TPA = 3 nM). TPA actions on adenylate cyclase were maximal after 15 min of incubation of the cells with the compound, correlating well with the time course of translocation of protein kinase C (Ca2+/phospholipid-dependent enzyme) from cytosol to membrane. The action of cholera toxin on adenylate cyclase was additive with TPA. In contrast, pertussis toxin actions on adenylate cyclase were not additive with TPA. Treatment of control cells with pertussis toxin activated adenylate cyclase 1.5-fold, whereas cells exposed to pertussis toxin for 6 h followed by TPA for 15 min showed the same 2-fold increase in adenylate cyclase activity as observed in membranes from cells exposed to TPA without prior exposure to pertussis toxin. Pertussis toxin catalyzed ADP-ribosylation was increased 2-fold in membranes from SCC 12F cells exposed to TPA, indicating an increase in the alpha beta gamma form of Gi. These data suggest that exposure of human keratinocytes to phorbol esters increases adenylate cyclase activity by a protein kinase C-mediated increase in the heterotrimeric alpha beta gamma form of Gi resulting in decreased inhibition of basal adenylate cyclase activity.
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PMID:Modulation of adenylate cyclase in human keratinocytes by protein kinase C. 246 Apr 60

Aggregation of marine sponge cells (Microciona prolifera) resembles stimulus-response coupling of higher organisms in which activation of protein kinase C and movements of intracellular Ca provide twin signals. We now report that activators of protein kinase C (phorbol esters) and ionomycin act synergistically to aggregate sponge cells. Surprisingly--since extracellular Ca is required for integrity of the species-specific aggregation factor--synergistic aggregation proceeded in the complete absence of added extracellular Ca (2.5-20 mM EDTA). The order of activity of phorbol esters and related compounds was that of their effect on protein kinase C (phorbol myristate acetate, phorbol dibutyrate greater than phorbol diacetate much greater than phorbol, 4 alpha-phorbol). 1-Oleyl, 2-acetylglycerol a synthetic activator of protein kinase C, also showed synergy with ionomycin. Phorbol esters and 1-oleyl, 2-acetylglycerol acted in synergy with ionomycin to liberate membrane Ca as detected by decreased fluorescence of chlortetracycline in prelabeled cells. Moreover, urushiol, the toxic principle of poison ivy, but not pentadecanylcatechol, its inert analogue, showed synergy with ionomycin. Synergistic aggregation was inhibited by calmidazolium (10 microM), piroxicam (20-100 microM), and pertussis toxin (20 micrograms/ml). The data not only confirm that marine sponge cell aggregation follows the general sequence of stimulus-response coupling in the cells of higher organisms but also support, in this most ancient of multicellular creatures, the hypothesis that mobilization of intracellular Ca and activation of protein kinase C provide the twin signals for cell activation in the absence of added extracellular Ca.
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PMID:Synergy between phorbol esters, 1-oleyl-2-acetylglycerol, urushiol, and calcium ionophore in eliciting aggregation of marine sponge cells. 345 50

1. Whole cell voltage-clamp techniques were used in the CA1 region of rat hippocampal slices to study presynaptic and postsynaptic gamma-aminobutyric acid B (GABAB) response mechanisms. The effects of the protein kinase C activator phorbol 12,13-diacetate (PDA), barium (Ba2+), and pertussis toxin were compared on the presynaptic and postsynaptic GABAB actions of bath-applied baclofen and paired-pulse depression (PPD) of the monosynaptic GABAA inhibitory postsynaptic current (IPSC). The magnitude of PPD was dependent on the amplitude of the first response. PPD was predominantly a GABAB-mediated effect, as it was very much reduced by the GABAB antagonist CGP 35348. 2. PDA enhanced monosynaptic GABAA IPSCs through an apparently presynaptic mechanism. Iontophoretic GABAA responses were unaffected, and there was no change in EIPSC. PDA increased the frequency of spontaneous, tetrodotoxin-insensitive IPSCs without significantly affecting their amplitudes. The inactive phorbol ester, 4 alpha-PDA did not alter IPSCs. After PDA application, stimulus intensity was adjusted to produce responses of comparable amplitude to control responses. PDA had a marked and reversible depressant effect on the postsynaptic GABAB response and caused a lesser, but still significant, reduction in the baclofen-induced reduction of monosynaptic IPSCs. PDA had no effect on PPD. 3. Ba2+ dramatically reduced postsynaptic GABAB responses; it had no effect on PPD. Ba2+ tended to decrease the presynaptic baclofen reduction of IPSCs, although this was not statistically significant. 4. Pertussis toxin, injected 2-3 days earlier into the intact hippocampus, blocked all three GABAB responses equally (approximately 70% decrease). 5. We conclude that presynaptic and postsynaptic GABAB mechanisms are mediated by G proteins that couple to different mechanisms. Discrepancies with previous work are evidently due to the use of different tissue preparations and different target responses. Even though protein kinase C activation caused a partial reduction in the presynaptic effect of baclofen, its lack of effect on PPD makes a significant role for protein kinase C in modulation of PPD unlikely.
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PMID:Differences between presynaptic and postsynaptic GABAB mechanisms in rat hippocampal pyramidal cells. 788 61

Altered polymorphonuclear leukocyte (PMN) function is thought to contribute to organ dysfunction during the systemic inflammatory response syndrome (SIRS). To test this hypothesis, we evaluated whole blood PMN function adherent to fibronectin or laminin in patients with mild or severe acute pancreatitis as a paradigm for sirs. Whole-blood PMN intracellular H2O2 production, expression of CD32w (Fc gamma R II), CD16 (Fc gamma R III), and phagocytosis were performed using dichlorofluorescein diacetate, fluorescein isothiocyanate-labeled anti-CD32w, CD16, and serum-opsonized fluorescent microspheres. Group I (n x 7) represents normal control individuals; group II (n x 11) represents patients with mild acute pancreatitis. Group III (n x 15) represents critically ill patients with severe acute pancreatitis. Adherence of PMN from groups I and II to matrix proteins resulted in a 5% to 20% increase in each PMN function assayed whereas adherence of PMN from group III to matrix proteins resulted in 50% to 75% increases in each PMN function assayed. Pertussis toxin, pentoxifylline, and dibutyryl cyclic adenosine monophosphate (cAMP) each reduced group I-II H2O2 production and phagocytosis. Pentoxifylline and dibutyryl cAMP but not pertussis toxin reduced group III H2O2 production. Both intracellular H2O2 and phagocytosis assays from group III but not groups I-II showed exaggerated upregulation when exposed to NaF (4 mmol/L). Anti-interleukin-6 reduced the increase in intracellular H2O2 production in group III patients and significantly altered the exaggerated oxidative response to NaF. Longitudinal studies of group III whole-blood PMN showed persistent upregulation of intracellular H2O2 production in those patients whose hospital courses were complicated by multiple system organ failure. These results demonstrate abnormal whole blood PMN function during the systemic inflammatory response syndrome in the presence of fibronectin, or laminin and that this is mediated in part via a pertussis toxin insensitive altered guanosine triphosphate-binding protein.
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PMID:Polymorphonuclear leukocyte dysregulation during the systemic inflammatory response syndrome. 811 41

Modulation of excitatory glutamatergic transmission at corticostriatal synapses by a metabotropic glutamate receptor (mGluR) was examined using a newly developed cell culture preparation in which small explants of cortical tissue are grown in co-culture with isolated striatal neurons. Electrical stimulation of cortical tissue evoked excitatory postsynaptic currents (eEPSCs) observed during tight-seal, whole-cell recordings from striatal neurons. Transmission was mediated by activation of AMPA/kainate-type glutamate receptors. The mGluR agonists, 1SR,3RS-ACPD and DCG-IV, reduced eEPSC amplitude. The effect of 1SR,3RS-ACPD increased in a concentration-dependent manner. Application of phorbol diacetate (PDAc) potentiated eEPSC amplitude and reduced the inhibitory effect of mGluR activation. Pretreatment with pertussis toxin (PTX) also reduced inhibition by 1SR,3RS-ACPD. Under conditions in which transmission was independent of the function of voltage-gated calcium channels, mGluR activation reduced the frequency of occurrence of miniature EPSCs (mEPSCs), but did not alter mEPSC amplitude. This effect of mGluR activation was reduced by PDAc treatment. mGluR activation modulates glutamatergic transmission via a presynaptic autoreceptor at corticostriatal synapses in this newly-developed corticostriatal co-culture preparation as in striatal slices. Modulation of transmission occurs whether or not transmission involves activation of voltage-gated calcium channels. Furthermore, many of the characteristics of mGluR modulation of eEPSCs are shared by mGluR modulation of mEPSCs. These findings indicate that mechanisms downstream from calcium entry may contribute to modulation of synaptic transmission by mGluR autoreceptors.
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PMID:Metabotropic glutamate receptor modulation of synaptic transmission in corticostriatal co-cultures: role of calcium influx. 853 75

We studied the effect of the adenylate cyclase activator forskolin, of protein kinase C-activating phorbol esters and of prolonged preganglionic input activation on the inhibitory response of the perfused superior cervical ganglion of the cat to exogenous met-enkephalin (Met-ENK). Met-ENK inhibited, in a concentration-dependent manner, the postganglionic compound action potential evoked by cervical sympathetic trunk stimulation. The inhibition was reversible, was blocked by naloxone as well as by pertussis toxin and showed no homologous desensitization in the concentration range 0.01-10 microM. Pretreatment of the ganglion with 4 beta-phorbol 12,13-dibutyrate or 4 beta-phorbol 12,13-diacetate depressed the Met-ENK response for several hours, while pretreatment with forskolin had no effect. This action of phorbol esters was prevented by the protein kinase inhibitor H-7 but not by the calmodulin antagonist W-7 or the protein kinase A inhibitor HA 1004 and was calcium-dependent. Recovery of the response from the depression produced by phorbol esters was not affected by a protein synthesis inhibitor. A 40 Hz 20 min stimulus train to the cervical sympathetic trunk mimicked the effect of phorbol esters, depressing for several hours the inhibition produced by Met-ENK. Stimulus trains of duration shorter than 5 min or frequency lower than 5 Hz were ineffective. This effect of prolonged preganglionic stimulation occurred even when the stimulus train was delivered during complete block of nicotinic and muscarinic ganglionic transmission but was lost when the stimulus train was delivered during perfusion with calcium-free Krebs. The protein kinase inhibitor H-7 prevented the depression of the Met-ENK response by the train, while W-7 and HA 1004 had no effect. These findings suggest that, in the superior cervical ganglion of the cat, a kinase, activated by phorbol esters and inhibited by H-7, exerts a long-term control of the ganglion cell responsiveness to opiate receptor activation. A similar mechanism can be synaptically activated by a non-cholinergic transmitter, released by the preganglionic axons during prolonged, high frequency, activity.
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PMID:Long-term depression of a sympathetic ganglionic response to opioids by prolonged synaptic activity and by phorbol esters. 896 46

In current Bordetella pertussis media ammonium accumulates because of an imbalance in the nitrogen:carbon ratio of the substrates used, which is one of the factors limiting cell density in fed-batch cultures. The aim of this study was to map B. pertussis catabolic and anabolic capabilities, in order to design a medium that avoids ammonium accumulation, while substrates are metabolised completely. Besides the known dysfunctional glycolysis, B. pertussis also possessed a partially dysfunctional citric-acid cycle. Although ammonium accumulation was avoided by adding various carbon sources to medium with glutamate, nuclear magnetic resonance (NMR) showed excretion of acetate, acetoacetate and beta-hydroxy-butyrate, thereby reducing the biomass yield. Acetoacetate and beta-hydroxy-butyrate were also formed in Verwey, B2 and modified Stainer-Scholte medium. Electron microscopy in combination with NMR showed that cells early on in these cultures contained poly-hydroxy-butyrate (PHB) globules, which disappeared later during the culture, coinciding with the appearance of beta-hydroxy-butyrate and/or acetoacetate. No globules nor metabolite excretion was detected when lactate in combination with glutamate were used as substrates. Thus, metabolite excretion and ammonium accumulation were avoided, while the yield of 8.8 g C-mol-1 compared favourably with literature values, averaging 6.5 g C-mol-1. Optimisation of this medium for pertussis toxin production will be reported in a separate article.
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PMID:Rational medium design for Bordetella pertussis: basic metabolism. 1055 54

Mastoparan, a widely used tetradecapeptide activator of Gi/Go G proteins, has been reported to be a potent co-mitogen for Swiss 3T3 fibroblasts. However, we have previously shown that the peptide promotes the release of lactate dehydrogenase from Swiss 3T3 cells and evokes only a modest and delayed increase in DNA. We suggested that the ability of the peptide to permeabilise these cells may account for its mitogenic action. Here we show that mastoparan caused a rapid release of fluorescein from cells which had been pre-incubated with fluorescein diacetate, indicating that the peptide increases membrane permeability to small molecules. Furthermore, the release of lactate dehydrogenase evoked by mastoparan was lost after prolonged (24 h) incubation of cells with the peptide. Together, these data indicate that mastoparan-induced cell permeabilisation is both rapid and transient. We have also shown that mastoparan increased c-fos mRNA accumulation and that this response was not influenced by pertussis toxin or indomethacin. Although mastoparan increased the intracellular calcium concentration, the removal of extracellular calcium had no effect on mastoparan stimulated c-fos mRNA accumulation. These data show that mastoparan-induced c-fos mRNA accumulation is not mediated by activation of a G protein and subsequent activation of phospholipase D nor by a non-selective increase in calcium influx. The data have significance for the interpretation of studies in which mastoparan is, or has been, used as an activator of Gi/Go.
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PMID:Mastoparan transiently permeabilizes Swiss 3T3 cells and induces c-fos proto-oncogene expression. Role of calcium and G protein activation. 1078 31


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