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

The acidic dipeptide N-acetylaspartylglutamate (NAAG) is the most prevalent peptide in the central nervous system. NAAG is a low potency agonist at the NMDA receptor, and hydrolysis of NAAG yields the more potent excitatory amino acid neurotransmitter glutamate. beta-NAAG is a competitive inhibitor of the NAAG hydrolyzing enzyme N-acetylated alpha-linked acidic dipeptidase (NAAG peptidase activity) or glutamate carboxypeptidase II, and may also act as a NAAG-mimetic at some of the sites of NAAG pharmacological activity. Since NAAG has been shown to have neuroprotective characteristics in a number of experimental preparations, it is the purpose of the present study to specifically evaluate the possible efficacy of NAAG and beta-NAAG against NMDA- and hypoxia-induced injury to spinal cord mixed neuronal and glial cell cultures. NAAG (500-1000 microM) protected against NMDA- or hypoxia-induced injuries to spinal cord cultures, and the nonhydrolyzable analog beta-NAAG (250-1000 microM) completely eliminated the loss of viability caused by either insult. Both peptides also attenuated NMDA-induced increases in intraneuronal Ca(2+). Nonspecific mGluR antagonists, pertussis toxin, a stable cAMP analog, and manipulation of NAAG peptidase activity did not by themselves alter cell damage and did not influence the neuroprotective effects of NAAG. NAAG was not protective against kainate- or AMPA-induced cellular injury, while beta-NAAG was partially neuroprotective against both insults. At 2 mM, NAAG and beta-NAAG reduced neuronal survival and increased intraneuronal Ca(2+); these effects were only marginally attenuated by dizocilpine and APV. The results indicate that NAAG and beta-NAAG protect against excitotoxic and hypoxic injury to spinal cord neurons, and do so predominantly by interactions with NMDA and not mGluR receptors.
 ...
PMID:N-acetylaspartylglutamate and beta-NAAG protect against injury induced by NMDA and hypoxia in primary spinal cord cultures. 1457 76

We have previously reported that dopamine (DA) depresses non-NMDA receptor-mediated glutamatergic transmission in the rat parabrachial nucleus (PBN), an interface between brainstem and forebrain that is implicated in autonomic regulation. This work examined cellular signalling pathways that might underlie this DA-induced synaptic depression. Direct activation of adenylyl cyclase with 10 microM forskolin increased the evoked EPSC but did not occlude DA-induced EPSC depression. Similarly, a preferential protein kinase A inhibitor, H-7 (10 microM), did not block DA's synaptic effects. Incubation of slices with cholera toxin (CTX; 1 microgram/ml) or pertussis toxin (PTX; 0.5 microgram/ml) for 20 h, procedures used to irreversibly activate or disable the G(s) and G(i) proteins, respectively, did not change DA's effects. The putative phospholipase C inhibitor, U-73122 (10 microM) and its inactive analogue U-73343 (10 microM) did not alter DA-induced reduction in the EPSCs. Alterations in signalling molecules downstream of phospholipase C including depleting internal calcium stores by thapsigargin and cyclopiazonic acid and blocking protein kinase C with chelerythrine, had no effect on DA-induced synaptic depression. Furthermore, DA's depression of the non-NMDA response was not blocked by APV, an NMDA receptor antagonist. Finally, DA depressed evoked, pharmacologically isolated NMDA receptor-mediated synaptic responses while increasing NMDA-induced inward currents in the PBN. These results indicate that DA-induced synaptic effects in the PBN are not through the activation of cholera or pertussis toxin sensitive G proteins. Furthermore, it does not employ the adenylyl cyclase-cAMP-PKA cascade, the phospholipase C signalling pathway and NMDA receptor-coupled mechanisms to depress excitatory synaptic transmission in the PBN.
 ...
PMID:Dopamine-induced synaptic depression in the parabrachial nucleus is independent of CTX- and PTX-sensitive G-proteins, PKA and PLC signalling pathways. 1467 13

In the presence of NMDA receptor open-channel blockers [Mg(2+); (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801); 1-amino-3,5-dimethyladamantane (memantine)] and TTX, high concentrations (30-100 microm) of either 5-hydroxytryptamine (5-HT) or alpha-methyl-5-hydroxytryptamine (alpha-Me-5-HT) significantly potentiated NMDA-induced depolarizations of frog spinal cord motoneurones. Potentiation was blocked by LY-53,857 (10-30 microm), SB 206553 (10 microm), and SB 204741 (30 microm), but not by spiroxatrine (10 microm), WAY 100,635 (1-30 microm), ketanserin (10 microm), RS 102221 (10 microm), or RS 39604 (10-20 microm). Therefore, alpha-Me-5-HT's facilitatory effects appear to involve 5-HT(2B) receptors. These effects were G-protein dependent as they were prevented by prior treatment with guanylyl-5'-imidodiphosphate (GMP-PNP, 100 microm) and H-Arg-Pro-Lys-Pro-Gln-Gln-D-Trp-Phe-D-Trp-D-Trp-Met-NH(2) (GP antagonist 2A, 3-6 microm), but not by pertussis toxin (PTX, 3-6 ng ml(-1), 48 h preincubation). This potentiation was not reduced by protein kinase C inhibition with staurosporine (2.0 microm), U73122 (10 microm) or N-(2-aminoethyl)-5-isoquinolinesulfonamide HCl (H9) (77 microm) or by intracellular Ca(2+) depletion with thapsigargin (0.1 microm) (which inhibits Ca(2+)/ATPase). Exposure of the spinal cord to the L-type Ca(2+) channel blockers nifedipine (10 microm), KN-62 (5 microm) or gallopamil (100 microm) eliminated alpha-Me-5-HT's effects. The calmodulin antagonist N-(6-aminohexyl)-5-chloro-1-naphtalenesulfonamide (W7) (100 microm) diminished the potentiation. However, the calcium/calmodulin-dependent protein kinase II (CaM Kinase II) blocker KN-93 (10 microm) did not block the 5-HT enhancement of the NMDA responses. In summary, activation of 5-HT(2B) receptors by alpha-Me-5-HT facilitates NMDA-depolarizations of frog motoneurones via a G-protein, a rise in [Ca(2+)](i) from the entry of extracellular Ca(2+) through L-type Ca(2+) channels, the binding of Ca(2+) to calmodulin and a lessening of the Mg(2+) -produced open-channel block of the NMDA receptor.
 ...
PMID:Mechanisms intrinsic to 5-HT2B receptor-induced potentiation of NMDA receptor responses in frog motoneurones. 1533 59

Apolipoprotein E is a genetic risk factor for Alzheimer's disease, and the apoE protein is associated with beta-amyloid deposits in Alzheimer's disease brain. We examined signaling pathways stimulated by apoE in primary neurons in culture. ApoE and an apoE-derived peptide activated several intracellular kinases, including prominently extracellular signal-regulated kinase 1/2 (ERK1/2). ERK1/2 activation by apoE was blocked by an inhibitor of the low-density lipoprotein receptor family, the specific NMDA glutamate receptor antagonist MK 801 and other calcium channel blockers. Activation of apoE receptors also induced tyrosine phosphorylation of Dab1, an adaptor protein of apoE receptors, but experiments in Dab1 knockout neurons demonstrated that Dab1 was not necessary for ERK activation. In contrast, apoE treatment of primary neurons decreased activation of c-Jun N-terminal kinase, a kinase that interacts with another apoE receptor adaptor protein, c-Jun N-terminal kinase-interacting protein. This change also depended on interactions with the low-density lipoprotein receptor family but was independent of calcium channels. c-Jun N-terminal kinase deactivation by apoE was blocked by gamma-secretase inhibitors and pertussis toxin. These results demonstrate that apoE affects several signaling cascades in neurons: increased disabled phosphorylation, activation of the ERK1/2 pathway (dependent on calcium influx via the NMDA receptor) and inhibition of the c-Jun N-terminal kinase 1/2 pathway (dependent on gamma-secretase and G proteins).
 ...
PMID:Multiple pathways of apolipoprotein E signaling in primary neurons. 1577 14

Abstract We have recently shown that glutamate primarily induces somatostatin release in hypothalamic neurons through N-methyl-D-aspartate (NMDA)-type receptor sites. Here we report that glutamate and NMDA also stimulate the release of [(3)H]arachidonic acid in a dose-dependent manner. The NMDA-induced effects (arachidonic acid release and somatostatin secretion) were both inhibited by MK-801, an NMDA receptor-type antagonist, or mepacrine, a phospholipase A(2) inhibitor. In addition, mepacrine was able to inhibit A23187-stimulated arachidonic acid release and somatostatin secretion. p-Bromophenacylbromide, another phospholipase A(2) inhibitor, also blocked NMDA-induced secretion of somatostatin. However, responses to NMDA were unaffected by H7 (inhibitor of protein kinase C), nordihydroguaiaretic acid or indomethacin (inhibitors of lipoxygenase and cyclooxygenase). Melittin, a phospholipase A(2) activator, was found to stimulate both responses, but omission of extracellular Ca(2+) from the incubation media strongly reduced melittin-induced somatostatin release. Six-h pertussis toxin pretreatment did not significantly reduce the action of NMDA on either of the two parameters studied. High-performance liquid chromatography analysis of [(3)H]metabolites released in the medium after NMDA stimulation revealed that [(3)H]arachidonic acid was the only detectable metabolite. External addition of arachidonic acid increased the release of somatostatin, whereas E(2) and F(2)alpha prostaglandins had no effect. Our results show a close correlation between arachidonic acid release and somatostatin secretion, the two parameters we investigated.
 ...
PMID:Phospholipase A and Somatostatin Release are Activated in Response to N-Methyl-D-Aspartate Receptor Stimulation in Hypothalamic Neurons in Primary Culture. 1921 1

Recently, we found that intrathecal (i.t.) pertussis toxin (PTX) injection produces thermal hyperalgesia and is associated with increasing concentrations of excitatory amino acids (EAAs) in spinal cerebrospinal fluid (CSF) dialysates; a reduction in the antinociceptive effects of morphine and glutamate transporters (GTs) was also observed. The reduction in the morphine-induced analgesic effects is directly related to increased extracellular EAA levels, which are maintained by GTs at physiological levels. In this study, we aimed to examine the role of GT isoforms in thermal hyperalgesia, determine the EAA concentrations in CSF dialysates, and elucidate the role of N-methyl-d-aspartate (NMDA) receptors in PTX-induced reduction in the antinociceptive effects of morphine. Two i.t. catheters and one microdialysis probe were inserted into male Wistar rats: one catheter was used for PTX (1 microg) and morphine (10 microg) injection and the other was connected to an osmotic pump for NMDA receptor antagonist d-2-amino-5-phosphonopentanoic acid (d-AP5; 2 microg/h for 4 days) continuous infusion. The microdialysis probe was used to collect CSF dialysates for EAA measurements by high-performance liquid chromatography. Intrathecal morphine failed to produce antinociceptive effects in PTX-treated rats, and d-AP5 coinfusion prevented the PTX-induced reduction in the antinociceptive effect and associated downregulation of the GTs. We conclude that NMDA receptor suppression inhibits EAA excitation and reduces the morphine-induced antinociception in PTX-treated rats.
 ...
PMID:N-Methyl-D-aspartate receptor antagonist d-AP5 prevents pertussis toxin-induced alterations in rat spinal cords by inhibiting increase in concentrations of spinal CSF excitatory amino acids and downregulation of glutamate transporters. 1946 18

Increased calcium influx secondary to glutamate induced excitotoxicity initiates and potentiates devastating pathological changes following ischemic stroke. Pertussis toxin (PTx), a G-protein blocker, is known to suppress intracellular calcium accumulation. We hypothesize that PTx can protect against stroke by blocking calcium influx. In a permanent middle cerebral artery occlusion model, PTx (1000 ng) was given intraperitoneally 30 min after inducing stroke. Magnetic Resonance Imaging of perfusion and T2-weighted brain scans were obtained to evaluate cerebral blood flow (CBF) and infarct volume. Primary neuronal culture was used to test glutamate induced excitotoxicity and calcium influx. We established a non-linear exponential curve model to minimize variations in animal cerebrovasculature. A reduction of 40-60% in relative CBF was a critical window where infarct volume started to increase as rCBF reduced. PTx showed maximal effects in reducing infarct volume at this window. In vitro studies further demonstrated PTx increased neuronal cell survival by decreasing glutamate-induced calcium influx into neurons and preventing neurons from apoptosis. PTx salvages the ischemic penumbra by blocking calcium influx. This provides us a new mechanism upon which experimental therapies can be explored to treat ischemic stroke. In ischemic stroke, excessive glutamate binds to AMPA receptor that depolarizes calcium channel and/ or NMDA receptor. Both of them allow calcium to enter the cell. The overload of calcium triggers cellular cascade that includes Caspase activation and release, leading to pre-mature cell death. We have demonstrated that PTx, a G-protein inhibitor, blocks calcium entry which in turn prevents further cellular damage.
 ...
PMID:Pertussis toxin reduces calcium influx to protect ischemic stroke in a middle cerebral artery occlusion model. 2636 74

Anti-N-methyl-d-aspartate (Anti-NMDA) receptor encephalitis is an acute autoimmune neurological disorder. The cause of this disease is often unknown, and previous studies revealed that it might be caused by a virus, vaccine or tumor. It occurs more often in females than in males. Several cases were reported to be related to vaccination such as the H1N1 vaccine and tetanus/diphtheria/pertussis and polio vaccines. In this study, we reported an anti-NMDA receptor encephalitis case that may be caused by Japanese encephalitis vaccination. To investigate the association between anti-NMDA receptor encephalitis and vaccination, we analyzed the phylogenetic relationship of the microRNAs, which significantly regulate these vaccine viruses or bacteria, and the phylogenetic relationship of these viruses and bacteria. This reveals that anti-NMDA receptor encephalitis may be caused by Japanese encephalitis vaccination, as well as H1N1 vaccination or tetanus/diphtheria/pertussis and polio vaccinations, from the phylogenetic viewpoint.
 ...
PMID:Anti-NMDA Receptor Encephalitis and Vaccination. 2810 87

Anti-N-methyl-D-aspartate (Anti-NMDA) receptor encephalitis is an acute autoimmune neurological disorder that can be triggered by virus, H1N1/tetanus/diphtheria/pertussis and polio vaccines or by presence of a tumor. The association between anti-NMDA receptor encephalitis and Japanese encephalitis vaccination was examined and a general protocol of phylogenetic method which details the steps and code and an example of its utility is provided. The approach used here is potentially useful for analyzing the relationship between vaccines and diseases.
 ...
PMID:A protocol for investigating the association of vaccination and anti-NMDA receptor encephalitis. 2893 May 29

Background: Anti-N-methyl D-aspartate (NMDA) receptor encephalitis is an autoimmune condition characterized by neuropsychiatric symptoms, including epileptic seizures, movement disorders, autonomic instability, disturbances of consciousness, paranoia, delusions, and catatonia. Ovarian teratomas and viral infections, typically Herpes simplex viruses, have previously been demonstrated to precipitate anti-NMDA receptor encephalitis, but in many cases, the trigger remains unclear. The detection of anti-NMDA receptor antibodies in cerebrospinal fluid (CSF), in combination with other CSF, electroencephalography (EEG), or magnetic resonance imaging (MRI) abnormalities, typically leads to diagnostic clarification. Case Presentation: We present the case of a 22-year-old female patient who developed an acute polymorphic psychotic episode 3 days after receiving a booster vaccination against tetanus, diphtheria, pertussis, and polio (Tdap-IPV). Her psychiatric symptoms were initially diagnosed as a primary psychiatric disorder. Her MRI, EEG, and CSF results were non-specific. Anti-NMDA receptor IgG antibodies against the GluN1 subunit were detected in her serum (with a maximum titer of 1:320), but not in her CSF. [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) showed pronounced relative hypermetabolism of her association cortices and a relative hypometabolism of the primary cortices, on the basis of which an anti-NMDA receptor encephalitis diagnosis was made, and treatment with a steroid pulse was initiated. The treatment led to fast and convincing clinical improvement with normalization of neuropsychological findings, considerable improvement of FDG-PET findings, and decreasing antibody titers. Conclusion: The patient's psychiatric symptoms were most likely caused by anti-NMDA receptor encephalitis. Her polymorphic psychotic symptoms first occurred after she had received a Tdap-IPV booster vaccination. Although the vaccination cannot have caused the initial antibody formation since IgG serum antibodies were detected only 3 days after administration of the vaccine, the vaccine may have exerted immunomodulatory effects. MRI, EEG, and CSF findings were non-specific; however, FDG-PET identified brain involvement consistent with anti-NMDA receptor encephalitis. This case shows the importance of implementing a multimodal diagnostic work-up in similar situations. The negative CSF antibody finding furthermore fits to the hypothesis that the brain may act as an immunoprecipitator for anti-NMDA receptor antibodies.
 ...
PMID:Psychiatric Presentation of Anti-NMDA Receptor Encephalitis. 3174 55


<< Previous 1 2 3 4 5 Next >>