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)

In pregnant-rat myometrium (day 21 of gestation), isoprenaline-induced cyclic AMP accumulation, resulting from receptor-mediated activation of adenylate cyclase, was negatively regulated by prostaglandins [PGE2, PGF2 alpha; EC50 (concn. giving 50% of maximal response) = 2 nM] and by the muscarinic agonist carbachol (EC50 = 2 microM). PG-induced inhibition was prevented by pertussis-toxin treatment, supporting the idea that it was mediated by the inhibitory G-protein Gi through the inhibitory pathway of the adenylate cyclase. Both isoprenaline-induced stimulation and PG-evoked inhibition of cyclic AMP were insensitive to Ca2+ depletion. By contrast, carbachol-evoked attenuation of cyclic AMP accumulation was dependent on Ca2+ and was insensitive to pertussis toxin. The inhibitory effect of carbachol was mimicked by ionomycin. Indirect evidence was thus provided for the enhancement of cyclic AMP degradation by a Ca2(+)-dependent phosphodiesterase activity in the muscarinic-mediated effect. The attenuation of cyclic AMP elicited by carbachol coincided with carbachol-stimulated inositol phosphate (InsP3, InsP2 and InsP) generation, which displayed an almost identical EC50 (3 microM) and was similarly unaffected by pertussis toxin. Both carbachol effects were reproduced by oxotremorine, whereas pilocarpine (a partial muscarinic agonist) failed to induce any decrease in cyclic AMP accumulation and concurrently was unable to stimulate the generation of inositol phosphates. These data support our proposal for a carbachol-mediated enhancement of a Ca2(+)-dependent phosphodiesterase activity, compatible with the rises in Ca2+ associated with muscarinic-induced increased generation of inositol phosphates. They further illustrate that a cross-talk between the two major transmembrane signalling systems contributed to an ultimate decrease in cyclic AMP in the pregnant-rat myometrium near term.
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PMID:Prostaglandins and muscarinic agonists induce cyclic AMP attenuation by two distinct mechanisms in the pregnant-rat myometrium. Interaction between cyclic AMP and Ca2+ signals. 170 Aug 99

Addition of the neuropeptide galanin to small cell lung cancer (SCLC) cells loaded with the fluorescent Ca2+ indicator fura-2-tetraacetoxymethylester causes a rapid and transient increase in the intracellular concentration of Ca2+ ([Ca2+]i) followed by homologous desensitization. Galanin increased [Ca2+]i in a concentration-dependent fashion with half-maximum effect (EC50) at 20-22 nM in H69 and H510 SCLC cells. Galanin mobilized Ca2+ from intracellular stores since its effects on [Ca2+]i were not blocked by chelation of extracellular Ca2+. Pretreatment with pertussis toxin (200 ng/ml for 4 h) did not prevent galanin-induced Ca2+ mobilization. In contrast, direct activation of protein kinase C with phorbol esters attenuated the Ca2+ response induced by galanin. The effects of galanin could be dissociated from changes in membrane potential: galanin did not increase membrane potential in SCLC cells loaded with bis(1,3-diethyltiobarbiturate)-trimethineoxonol and induced Ca2+ mobilization in depolarized SCLC cells, i.e., in cells suspended in a solution containing 145 mM K+ instead of Na+. Galanin also caused an increase in the formation of inositol phosphates in a time- and dose-dependent manner (EC50 10 nM). A rapid increase in the inositol trisphosphate fraction was followed by a slower increase in the inositol monophosphate fraction. Galanin stimulated clonal growth of both H69 and H510 cells in semisolid (agarose-containing) medium. This growth-promoting effect was sharply dependent on galanin concentration (EC50 20 nM) and markedly inhibited by [Arg6,D-Trp7,9,MePhe8]substance P, a recently identified broad spectrum neuropeptide antagonist. The results show for the first time that galanin receptors are coupled to inositol phosphate and [Ca2+]i responses in SCLC cells and, in particular, that this neuropeptide can act as a direct growth factor for these human cancer cells.
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PMID:Galanin stimulates Ca2+ mobilization, inositol phosphate accumulation, and clonal growth in small cell lung cancer cells. 170 78

Substance P (SP) stimulates polyphosphoinositide breakdown in the rat anterior pituitary through an NK-1 receptor. In the present study we present evidence that the coupling between the SP-NK1 receptor complex and polyphosphoinositide-specific phospholipase C (PI-PLC) in rat anterior pituitary membranes may involve a mechanism consistent with a GTP-binding protein. The formation of inositol phosphates from [3H]myo-inositol-labelled anterior pituitary membranes induced by SP was potentiated by GTP and non-hydrolysable guanine nucleotides. The stimulatory effects of SP alone and SP plus GTP could be blocked by addition of GDP-beta-S (guanosine 5-O-(thiodiphosphate] in excess. Basal and SP plus guanine nucleotide-induced inositol phosphate formation were stimulated by fluoride, whereas the effect of SP alone was inhibited. Pretreatment of anterior pituitary membranes with sodium deoxycholate attenuated the inositol phosphate response elicited by GTP and GTP-gamma-S, whereas basal and SP-stimulated inositol phosphate production showed a peak at 1 mg sodium deoxycholate/ml. SP, fluoride and guanine nucleotide stimulatory effects on hydrolysis of polyphosphoinositide (PPI) were unaffected by pretreatment of anterior pituitary cells with cholera or pertussis toxin for 12h. Treatment of anterior pituitary membranes with cholera and pertussis toxin yielded [32P]ADP-ribosylation of two proteins with molecular masses of 45 and 41 kDa respectively. We conclude that SP coupling to PI-PLC through the NK1 receptor in the rat anterior pituitary involves a GTP-binding mechanism distinct from the G-proteins associated with adenylate cyclase, Gs and Gi.
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PMID:Substance P stimulation of polyphosphoinositide hydrolysis in rat anterior pituitary membranes involves a GTP-dependent mechanism. 171 80

Bombesin (BB), neuromedin C (NMC) and neuromedin B (NMB) stimulated amylase secretion to similar maximum levels, with EC50 values (concentrations causing 50% of maximum effect) of 0.2, 0.3 and 2 nM respectively. Treatment of pancreatic acini with BB or NMB (10 nM) for 30 min resulted in cross-desensitization of secretory responses to subsequent BB and NMB, but not to acetylcholine, which suggests that NMB and BB activate the same receptor. BB, NMC and NMB stimulated production of similar maximum amounts of inositol mono-, bis- and tris-phosphates, with EC50 values of 3, 5 and 141 nM respectively. The bombesin receptor antagonist [Leu13-psi(CH2NH)Leu14]BB inhibited stimulation of amylase secretion and inositol phosphate formation by BB, NMC and NMB. Binding of 125I-labelled gastrin-releasing peptide (GRP; 200 pM) to rat pancreatic membranes at 22 degrees C was inhibited with relative potencies and IC50 (concn. causing 50% of maximal inhibition; nM) as follows: NMC (0.4) = BB (0.5) greater than NMB (1.8 = GRP (2.6). IC50 values for BB, NMC and NMB inhibition of 125I-GRP binding to intact acini were 5-, 19- and 68-fold higher than their respective values in membranes. The guanine nucleotide analogue guanosine 5'-[beta gamma-imido]triphosphate (Gpp[NH]p) produced rightward shifts of NMC and NMB competition curves by 3.5- and 16-fold respectively, but had little effect on the BB and GRP curves. Elevation of the temperature to 37 degrees C or inclusion of NaCl (40 mM) produced quantitatively similar effects to those of Gpp[NH]p. In the presence of both NaCl and Gpp[NH]p the affinities of peptides for membrane receptors were similar to those for intact cells. Modulation of NMB competition curves by Gpp[NH]p was not attenuated by prior treatment of acini with activated pertussis toxin. These results suggest that BB, NMB and NMC stimulate pancreatic secretion by interaction with a common phosphoinositide-linked receptor. Differences in guanine nucleotide regulation suggest that secretagogue-induced receptor-protein interactions may not be identical for NMB and BB.
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PMID:Bombesin, neuromedin B and neuromedin C interact with a common rat pancreatic phosphoinositide-coupled receptor, but are differentially regulated by guanine nucleotides. 172 Jun 12

Endothelin (ET)-related peptides robustly stimulated [3H]-inositol phosphate (IP) formation in cultured cerebellar granule cells, astrocytes, and C6 glioma cells. Their agonist selectivities were ET-1 = ET-2 greater than or equal to sarafotoxin S6b greater than ET-3 greater than big ET-1 for granule cells and ET-1 greater than or equal to ET-2 greater than or equal to S6b greater than big ET-1 greater than ET-3 for cerebellar astrocytes and C6 glioma cells. These effects were Ca(2+)-dependent but insensitive to antagonists of L-type Ca2+ channels and the Na+/Ca2+ antiporter. Pretreatment of cells with ET-1 or S6b induced homologous desensitization of phosphoinositide (PI) response mediated by ET receptors. Long-term pertussis toxin (PTX) treatment attenuated the phosphoinositide (PI) response in astrocytes and glioma but not in granule cells. ET-1 and its related peptides increased [Ca2+]i in C6 glioma by two distinct pathways: IP3-induced Ca2+ mobilization or receptor-operated Ca2+ influx. La3+, Mn2+, and Cd2+ inhibited the Ca2+ influx and sustained PI turnover, while Ca2+ mobilization was attenuated by phorbol ester and TMB-8. ET-induced Ca2+ influx was essential for the sustained [Ca2+]i increase and PI turnover. Homologous desensitization of [Ca2+]i increase was also noted. In cerebellar granule cells, ET evoked the release of [3H]D-aspartate from these neurons. This action appears to be dependent on PI hydrolysis and [Ca2+]i increase and modulated by protein kinase C.
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PMID:Endothelin-induced activation of phosphoinositide turnover, calcium mobilization, and transmitter release in cultured neurons and neurally related cell types. 172 40

We performed a double-blind, randomized trial to compare the immunogenicity and reactogenicity of four conjugate Haemophilus influenzae type b vaccines given to infants 2, 4, and 6 months of age. Adverse reactions attributable to the vaccines were few and minor. The rates of systemic reactions did not differ among the various vaccines and were similar to those seen among children receiving conventional diphtheria-tetanus-pertussis vaccine. However, the four conjugate H. influenzae type b vaccines differed markedly in ability to stimulate antibody production. Mean antibody levels after three injections of polyribosylribitol phosphate conjugated with mutant diphtheria protein (PRP-CRM) or polyribosylribitol phosphate conjugated with tetanus toxoid (PRP-T) were 3.08 micrograms/ml and 3.64 micrograms/ml, respectively, significantly higher than those after the use of polyribosylribitol phosphate conjugated with outer-membrane protein of Neisseria meningitidis (PRP-OMP) (1.14 micrograms/ml) or polyribosylribitol phosphate conjugated with diphtheria toxoid (PRP-D) (0.28 microgram/ml). Only PRP-OMP produced a clinically pertinent elevation in antibody level after two injections (0.84 microgram/ml); the third injection of PRP-OMP produced a modest but statistically significant further elevation in mean antibody level (1.14 micrograms/ml). Only 29% of infants receiving PRP-D had antibody levels of 1 micrograms/ml, compared with 55%, 75%, and 83% of those receiving PRP-OMP, PRP-CRM, and PRP-T, respectively. We conclude that all four vaccines are safe and that all but PRP-D appear appropriate for use in a primary immunization series during infancy. The unique serologic response to PRP-OMP offers both advantages and disadvantages in comparison with PRP-CRM and PRP-T.
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PMID:Comparative trial in infants of four conjugate Haemophilus influenzae type b vaccines. 162 87

Mononuclear phagocytes infected with Leishmania have been shown to have defective responses to extracellular stimuli. To investigate the potential relationship of these findings to alterations in calcium-dependent signaling pathways, the regulation of [Ca2+]i concentrations was examined in human peripheral blood monocytes infected with amastigotes of Leishmania donovani. Measurements of [Ca2+]i in fura-2-loaded monocytes were made at the single cell level by microfluorimetry. In normal monocytes, resting [Ca2+]i was 56 +/- 2 nM (mean +/- SEM). In contrast, in monocytes infected with Leishmania there was an approximately twofold increase in basal [Ca2+]i (122 +/- 5 nM, p less than 0.01 vs control). Treatment of cells with pertussis toxin before infection did not abrogate infection-induced increases in basal [Ca2+]i, suggesting that this effect was not mediated via the activation of a G protein coupled to phospholipase C. However, elevated resting [Ca2+]i did correlate with increased rates of 45Ca2+ uptake by infected monocytes. As expected, in response to treatment with 10(-7) M FMLP, control monocytes showed rapid net increases in [Ca2+]i of 303 +/- 19 nM. In contrast, net transients of [Ca2+]i in infected monocytes in response to FMLP were attenuated to only 137 +/- 9 nM (p less than 0.01 vs control). This result was not related to excess buffering of [Ca2+]i in infected cells as both control and infected monocytes showed equivalent transients of [Ca2+]i in response to the calcium ionophore A23187. Rather, inhibition of agonist-induced calcium release in infected cells appeared related to defective generation of second messenger because compared to control cells labeled with myo-[2-3H]inositol, little accumulation of inositol 1,4,5-trisphosphate was detected in infected monocytes. Attenuation of inositol phosphate accumulation and calcium release in response to chemotactic peptide correlated with decreased FMLP-induced superoxide and hydrogen peroxide production by infected monocytes. These results provide direct evidence for defective regulation of [Ca2+]i and calcium-dependent signaling in Leishmania-infected monocytes and provide a basis for understanding abnormalities in activation-related responses that involve signaling through Ca(2+)-regulated pathways.
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PMID:Stimulus-response coupling in monocytes infected with Leishmania. Attenuation of calcium transients is related to defective agonist-induced accumulation of inositol phosphates. 173 35

Reactions to adsorbed diphtheria-pertussis-tetanus (DPT) vaccine have mostly been attributed to the pertussis organisms or pertussis components in the vaccine. Nevertheless reactions may also be due to other factors such as sensitization induced by aluminium adjuvants and impurities present in crude toxoids that cannot be removed by purification of toxoids after formalinization. Aluminium compounds such as aluminium phosphate and aluminium hydroxide are the most commonly used adjuvants with vaccines for human use. Due to the increasing concern about the toxicity of aluminium, other adjuvants like calcium phosphate may be evaluated as an alternative to aluminium adjuvants. To minimize reactions after immunization with DPT vaccine due to impurities in the toxoids, the use of toxoided purified toxins is suggested.
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PMID:Adverse reactions after injection of adsorbed diphtheria-pertussis-tetanus (DPT) vaccine are not due only to pertussis organisms or pertussis components in the vaccine. 175 87

Extracellular nucleotides, acting through P2 purinoceptors, have been implicated in the regulation of ion transporting epithelia, including salivary gland acini. Multiple P2 purinoceptor subtypes have been suggested, including P2X, P2Y and P2U (or nucleotide) subtypes, as well as the P2Z subtype found in rat parotid acinar cells. We investigated responses to ATP, ATP analogs and UTP in transformed human submandibular gland duct cells (HSG-PA), in order to compare duct cell purinoreceptors with those in acinar cells. ATP, UTP and some ATP analogs increased, with different potencies, inositol phosphate accumulation, calcium mobilization and potassium efflux. Nucleotide-stimulated calcium mobilization occurred in the absence of, but was enhanced by, extracellular calcium, and maximal potassium efflux required extracellular calcium. UTP and ATP demonstrated equal potencies of about 1 microM and similar efficacies in eliciting these responses, and identical rank orders of potency for stimulating calcium mobilization and potassium efflux were obtained: UTP = ATP greater than ATP gamma S greater than ADP greater than ADP beta S, with alpha,beta-methylene-ATP and 2-methylthio-ATP having little or no effect. Agents reported to block nucleotide effects in parotid acini were ineffective in HSG-PA cells, and experiments in Mg(++)- and Ca(++)-free medium did not indicate that a form of ATP other than MgATP was the active species at the HSG-PA purinoceptor. The extracellular nucleotide effects were not altered by pertussis toxin. These results indicate the presence of a P2U or nucleotide receptor subtype in HSG-PA submandibular duct cells distinguishable from the P2Z purinoceptor of rat parotid acinar cells, suggesting involvement of multiple nucleotide receptor subtypes in salivary gland regulation.
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PMID:Functional studies in the human submandibular duct cell line, HSG-PA, suggest a second salivary gland receptor subtype for nucleotides. 176 82

Lipopolysaccharides (LPS) isolated from Bordetella pertussis (Bp), B. parapertussis (Bpp), and B. bronchiseptica (Bbs) were analysed for their chemical composition, molecular heterogeneity, and immunological and biological properties. All LPS contained heptose, KDO, GlcN, uronic acid, phosphate, and fatty acids. The fatty acids C14:0, C16:0 and 3-OHC14:0 were common to all LPS preparations. By SDS-PAGE, Bp-LPS had two bands of low molecular mass, and Bpp- and Bbs-LPS showed a low molecular mass band together with ladder bands of high molecular mass. Immunological assays demonstrated that Bp-LPS reacted with antisera prepared from Bp and Bpp; Bpp-LPS reacted with antisera against Bpp and Bbs, and Bbs-LPS reacted with antisera against any of the three species. Bp-LPS showed biological activities comparable to those of E. coli LPS in terms of lethal toxicity, pyrogenicity, mitogenicity, macrophage activation, and induction of tumor necrosis factor. All activities of Bpp-LPS, except mitogenicity, were lower than those of E. coli LPS. Biological activities stronger or comparable to those of E. coli LPS were observed for Bbs-LPS.
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PMID:Structural and biological comparison of lipopolysaccharides (LPS) from Bordetella species. 177 13


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