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)

Pertussis toxin (PTX), which causes the ADP-ribosylation and thereby inactivation of Gi-proteins, has been employed in analgesia testing to elucidate receptors that are coupled to inhibitory G-proteins, such as the mu-opioid receptor. Consistent with previous findings, the antinociceptive effects of morphine (1-10 microg) as measured by tail-flick latency using a 55 degrees C water bath, were blocked by a single intrathecal injection of 0.5 microg PTX 6 days prior to intrathecal morphine administration. In addition, mice treated intrathecally with 0.5 microg of PTX had significantly shorter baseline tail-flick latencies compared with vehicle treated mice using a 55 degrees C water bath when tested 6 days after PTX or vehicle administration. Morphine-induced antinociception was blocked in a dose-dependent manner by PTX with complete blockade of morphine following a 0.3-microg dose of PTX. Further, mice administered 0.1 microg or 0.3 microg PTX intrathecally had significantly shorter tail-flick latencies compared with vehicle injected mice using a 40, 45 or 50 degrees C water bath when tested 7 days after intrathecal injection. Shorter tail-flick latencies were observed at 45 degrees C as early as 48 h after intrathecal administration of 0.03, 0.1 or 0.3 microg PTX and these shorter tail-flick latencies were observed up to 90 days after intrathecal PTX administration. The intrathecal administration of PTX caused hyperalgesia and allodynia that appears similar to the symptoms reported by patients suffering from neuropathic pain, and suggests that deficiencies in inhibitory systems, as compared with increases in excitatory systems, may play a role in the pathophysiology of at least some central or neuropathic pain states.
Pain 1997 Apr
PMID:Intrathecal pertussis toxin produces hyperalgesia and allodynia in mice. 915 Feb 97

Opiates have been used extensively in the treatment of pain but with the severe side effect of addiction, which is believed to be related to opiates' direct (primary) or indirect (secondary) neurotoxicity. In this study, the effects of opioids on cell growth and apoptosis have been examined in human neuroblastoma cell line SK-N-SH. Etorphine, a wide-spectrum and potent agonist of opioid receptors, was found to significantly inhibit cell growth and to induce apoptosis. The inhibitory and apoptotic activities of etorphine followed a dose- and time-dependent manner. The more specific agonists of opioid receptors such as morphine, [D-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin (DAGO), [D-Pen2, D-Pen5]-enkephalin (DPDPE), dynorphin A and nociceptin/orphanin FQ did not show similar toxic activities under the same conditions. In addition, the effects of etorphine could not be blocked by the opioid receptor antagonist naloxone, suggesting that the effects of etorphine might not be mediated by a classical opioid receptor. However, pretreatment of SK-N-SH cells with pertussis toxin (PTX) blocked the inhibition of cell growth and apoptosis induced by etorphine, indicating the involvement of PTX-sensitive G proteins in the processes. It was also shown that etorphine-induced apoptosis was prevented by actinomycin D (AD) and interleukin-1beta converting enzyme inhibitor I. Interestingly, etorphine was similarly potent to inhibit growth of pheochromocytoma (PC12) cells but less effective in SH-SY5Y neuroblastoma cells and C6 glioma cells. We propose that inhibition of cell growth and induction of apoptosis may be one mechanism of opioid neurotoxicity.
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PMID:Etorphine inhibits cell growth and induces apoptosis in SK-N-SH cells: involvement of pertussis toxin-sensitive G proteins. 935 60

Anandamide is an endogenous ligand of cannabinoid receptors that induces pharmacological responses in animals similar to those of cannabinoids such as delta9-tetrahydrocannabinol (THC). Typical pharmacological effects of cannabinoids include disruption of pain, memory formation, and motor coordination, systems that all depend on NMDA receptor mediated neurotransmission. We investigated whether anandamide can influence NMDA receptor activity by examining NMDA-induced calcium flux (deltaCa2+NMDA) in rat brain slices. The presence of anandamide reduced deltaCa2+NMDA and the inhibition was disrupted by cannabinoid receptor antagonist, pertussis toxin treatment, and agatoxin (a calcium channel inhibitor). Whereas these treatments prevented anandamide inhibiting deltaCa2+NMDA, they also revealed another, underlying mechanism by which anandamide influences deltaCa2+NMDA. In the presence of cannabinoid receptor antagonist, anandamide potentiated deltaCa2+NMDA in cortical, cerebellar, and hippocampal slices. Anandamide (but not THC) also augmented NMDA-stimulated currents in Xenopus oocytes expressing cloned NMDA receptors, suggesting a capacity to directly modulate NMDA receptor activity. In a similar manner, anandamide enhanced neurotransmission across NMDA receptor-dependent synapses in hippocampus in a manner that was not mimicked by THC and was unaffected by cannabinoid receptor antagonist. These data demonstrate that anandamide can modulate NMDA receptor activity in addition to its role as a cannabinoid receptor ligand.
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PMID:Dual effects of anandamide on NMDA receptor-mediated responses and neurotransmission. 945 61

The G protein Go is highly expressed in neurons and mediates effects of a group of rhodopsin-like receptors that includes the opioid, alpha2-adrenergic, M2 muscarinic, and somatostatin receptors. In vitro, Go is also activated by growth cone-associated protein of Mr 43,000 (GAP43) and the Alzheimer amyloid precursor protein, but it is not known whether this occurs in intact cells. To learn about the roles that Go may play in intact cells and whole body homeostasis, we disrupted the gene encoding the alpha subunits of Go in embryonic stem cells and derived Go-deficient mice. Mice with a disrupted alphao gene (alphao-/- mice) lived but had an average half-life of only about 7 weeks. No Goalpha was detectable in homogenates of alphao-/- mice by ADP-ribosylation with pertussis toxin. At the cellular level, inhibition of cardiac adenylyl cyclase by carbachol (50-55% at saturation) was unaffected, but inhibition of Ca2+ channel currents by opioid receptor agonist in dorsal root ganglion cells was decreased by 30%, and in 25% of the alphao-/- cells examined, the Ca2+ channel was activated at voltages that were 13.3 +/- 1.7 mV lower than in their counterparts. Loss of alphao was not accompanied by appearance of significant amounts of active free betagamma dimers (prepulse test). At the level of the living animal, Go-deficient mice are hyperalgesic (hot-plate test) and display a severe motor control impairment (falling from rotarods and 1-inch wide beams). In spite of this deficiency, alphao-/- mice are hyperactive and exhibit a turning behavior that has them running in circles for hours on end, both in cages and in open-field tests. Except for one, all alphao-/- mice turned only counterclockwise. These findings indicate that Go plays a major role in motor control, in motor behavior, and in pain perception and also predict involvement of Go in Ca2+ channel regulation by an unknown mechanism.
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PMID:Multiple neurological abnormalities in mice deficient in the G protein Go. 950 Dec 52

An acidic antitumor glycoprotein (SAGP) was purified from a crude extract of Streptococcus pyogenes, Su strain. Intraperitoneal injection with SAGP (20 mg protein/kg/day for 4 consecutive days) prolonged the life span of mice inoculated i.p. with Ehrlich ascite carcinoma cells and methylcholanthrene-induced fibrosarcoma cells (Meth A) up to 244% and 169% of that of the control mice, respectively. These in vivo antitumor effects were reduced in immunosuppressed mice. The effector spleen cells from the Meth A-inoculated and SAGP-injected mice showed a considerable cytostatic activity on Meth A cells in vitro, and immunosuppression studies suggested that carrageenan-sensitive and/or asialo-GM1 positive spleen cells are responsible for the in vivo antitumor effect of SAGP. SAGP inhibited the cell growth of cultured cell lines including transformed hamster embryonic lung cells, murine leukemia L 1210, Meth A and human promyelocytic leukemia HL60 cells. The IC50s for the cell growth of these cells were all below 0.1 microg protein/ml. SAGP inhibited the incorporation of nucleic acid precursors into Meth A cells. It seems that sulfhydryl groups of the SAGP molecule are essential for the expression of the antitumor action of SAGP. The cell growth-inhibitory activity of SAGP was diminished in Meth A cells preincubated with pertussis toxin (IAP), whereas it was augmented in the cells preincubated with cholera toxin (CTX), suggesting the involvement of toxin-sensitive GTP (G)-proteins in the SAGP-action. IAP and CTX-catalyzed ADP ribosylation assays confirmed that SAGP augmented the activity of IAP-sensitive G-protein. In addition, this augmentation was detected neither in Meth A cells incubated with heat-inactivated SAGP nor in SAGP-insensitive L929 cells. SAGP induced apoptosis in Meth A and HL60 cells as assessed by DNA fragmentation. A single dose injection of SAGP (100 mg protein/kg, i.v., s.c., or i.p.) into mice produced no toxic signs except occasional pain responses observed for one week after the injection. Thus, SAGP is a low toxic substance that shows in vivo antitumor activity by modulating immune responses of the host, and also exhibits in vitro cell-growth inhibition through IAP-sensitive G-protein.
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PMID:Characterization of a streptococcal antitumor glycoprotein (SAGP). 951 6

The reactogenicity and immunogenicity of a tetravalent diphtheria-tetanus-acellular pertussis-hepatitis B (DTPa-HB) vaccine (SmithKline Beecham) were studied in 565 infants immunized according to one of two different schedules, at 2, 4 and 6 months of age (group A n = 208) or at 3, 5 and 11 months of age (group B n = 357). The incidences of local and general reactions within the first 8 days after vaccination were similar in the two groups of infants, the vast majority being mild in intensity and occurring within 2-3 days of vaccine administration. Severe local symptoms were rare: pain after 0.6% of all doses, redness after 0.5% and 1.3%, and swelling after 0.3% and 1.5%, in group A and B, respectively. Only one infant in group A and one in group B had a temperature > 39.0 degrees C. Both schedules proved satisfactory in obtaining high levels of antibodies against all antigens. The rates of serologic response against the different antigens reached 100% in both groups. Antibody titres against all vaccine components were elevated following both schedules, but after the third dose of vaccine geometric mean antibody titres (GMTs) against D toxoid, filamentous haemagglutinin (FHA), pertactin (PRN) and hepatitis B (HB) were significantly higher in the 3, 5, 11 group than after the 2, 4, 6 schedule. Antibody titres measured at 7 months of age in the group immunized at 2, 4 and 6 months were higher than those reached at 6 months of age in infants immunized at 3, 5 and 11 months, but FHA and PRN were within the range of DTPa vaccine with proven efficacy. We conclude that DTPa-HB vaccine was safe, well tolerated and highly immunogenic. Both vaccination schedules (2, 4, 6 and 3, 5, 11) can be considered suitable for mass immunization programmes.
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PMID:Safety and immunogenicity of a combined diphtheria-tetanus-acellular pertussis-hepatitis B vaccine administered according to two different primary vaccination schedules. Multicenter Working Group. 956 92

Dipyrone injected intraperitoneally (i.p.) or subplantarly into the mouse paw caused dose-related antinociception against the early and the late phases of formalin-induced licking, with mean ID50 values of 154.5 and 263.7 micromol/kg, and 2.6 and 1.2 micromol/paw, respectively. Given either by intracerebroventricular (i.c.v.) or by intrathecal (i.t.) routes, dipyrone produced a similar inhibition of both phases of the formalin-induced licking, with mean ID50 values of 0.4 and 1.3 micromol/site, and 0.4 and 0.9 micromol/site against the early and the late phase of the formalin response, respectively. Dipyrone, given by i.p., subplantar, i.t. or i.c.v. routes, caused dose-related antinociception of capsaicin-induced licking. The mean ID50 values were: 207.6 micromol/kg, 2.2 micromol/paw, 0.4 micromol/site and 0.14 micromol/site, respectively. In addition, dipyrone given i.p. caused a significant increase of the latency both in the hot-plate and the tail-flick assays. Dipyrone, given i.p., i.t. or i.c.v., reversed significantly the hyperalgesia caused by i.t. injection of glutamate, with mean ID50 values of 9 micromol/kg, 29 nmol/site and 94 nmol/site, respectively. The antinociception caused by dipyrone was not influenced by naloxone, L-arginine, phaclofen, glibenclamide, p-chlorophenylalanine methyl ester, pertussis toxin or by adrenal gland hormones, when assessed against the formalin assay. Dipyrone analgesic action was not secondary to its anti-inflammatory effect, nor was it associated with non-specific effects such as muscle relaxation or sedation actions of animals. Dipyrone at a higher concentration caused significant inhibition of [3H]glutamate binding (37%) in cerebral cortical membranes from both mice and rats. However, dipyrone had no significant effect on brain constitutive neuronal nitric oxide synthase activity. It is concluded that dipyrone produces peripheral, spinal and supraspinal antinociception when assessed on formalin and capsaicin-induced pain as well as in glutamate-induced hyperalgesia in mice. Dipyrone antinociception seems unlikely to involve an interaction with the L-arginine-nitric oxide pathway, serotonin system, activation of Gi protein sensitive to pertussis toxin. interaction of ATP-sensitive K+ channels, GABA(B) receptors, or the release of endogenous glucocorticoids. However, a modulatory effect on glutamate-induced hyperalgesia and, to a lesser extent, an interaction with glutamate binding sites, seems to account for its analgesic action.
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PMID:Spinal and supraspinal antinociceptive action of dipyrone in formalin, capsaicin and glutamate tests. Study of the mechanism of action. 959 21

We have studied the in vivo signaling mechanisms involved in nociceptin/orphanin FQ (Noci)-induced pain responses by using a flexor-reflex paradigm. Noci was 10,000 times more potent than substance P (SP) in eliciting flexor responses after intraplantar injection into the hind limb of mice, but the action of Noci seems to be mediated by SP. Mice pretreated with an NK1 tachykinin receptor antagonist or capsaicin, or mice with a targeted disruption of the tachykinin 1 gene no longer respond to Noci. The action of Noci appears to be mediated by the Noci receptor, a pertussis toxin-sensitive G protein-coupled receptor that stimulates inositol trisphosphate receptor and Ca2+ influx. These findings suggest that Noci indirectly stimulates nerve endings of nociceptive primary afferent neurons through a local SP release.
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PMID:Nociceptin/orphanin FQ-induced nociceptive responses through substance P release from peripheral nerve endings in mice. 972 10

In an effort to determine the optimal dose of pertussis toxoid (PT) and filamentous haemagglutinin (FHA) for use in acellular pertussis vaccines we compared the immunogenicity and safety of acellular pertussis vaccine combined with diphtheria and tetanus toxoids containing 12.5 microg (DTaP-12.5) or 25 microg (DTaP-25) each of PT and FHA with a whole cell pertussis vaccine in infants immunized at 2, 4 and 6 months of age. Recipients of acellular vaccines developed higher anti-FHA concentrations and more rapid anti-PT serological responses that infants who received whole cell pertussis vaccine combined with diphtheria and tetanus toxoids (DPT). A dose response was noted; infants immunized with DTaP-25 developed significantly (P<0.03) higher anti-FHA and anti-PT levels than infants who received DTaP-12.5. No rise in the agglutinin titres was noted for recipients of the acellular vaccines although this vaccine stimulated increases in agglutinins when given as the fourth or fifth dose to children who had received three doses of DTP. The rates of erythema, induration, pain, irritability, crying, increased sleepiness, and decreased appetite were significantly (P</=0.05) lower in infants who received acellualr vaccines than in infants who received DTP. When the data from the injections at 2, 4 and 6 months of age were combined, no significant differences in the rates of any adverse event were noted for recipients of DTaP-12.5 or DTaP-25. The rates of most adverse reactions following DTP decreased from the first to the third immunization except fever, which increased. For acellular vaccine recipients, the rates of fever and erythema increased somewhat from the first to the third injection but remained far below the rates following DTP. The acellular vaccine was safe and immunogenic, and a dose-response effect was demonstrated.
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PMID:Dose-response to a two-component acellular pertussis vaccine in infants and comparison with whole-cell vaccine. 981 22

In this review we critically appraise the value of some phasic and tonic nociceptive tests as models for differentiating the antinociceptive effects of opioid agonists. Using heat-evoked withdrawal of the hind paw or tail of a rodent, several early studies have assessed the effects of stimulus intensity upon antinociceptive potency of opioid agonists. After intrathecal (i.t.) administration of either morphine or sufentanil, for example, for any incremental change in stimulus intensity, the degree of right shift in the dose-response relationship was greater for morphine than for sufentanil. At first glance, such data appear to provide robust support for the pharmacological model of fractional receptor occupancy (FRO), which, according to the historical tenets of classical receptor theory, describes the relationship between intrinsic efficacy and the total receptor concentration. However, new data which elegantly characterize the relative contribution of small calibre unmyelinated and myelinated nociceptive afferents in mediating thermal-evoked responses challenge the exclusivity of such explanations with origins in classical theory. Within our review we report the results of experiments which provide direct electrophysiological evidence that noxious skin heating at a low rate activates C-polymodal nociceptors, but does not effectively activate A-delta mechanothermal nociceptors. In contrast, a high rate of skin heating activates both nociceptor classes, but produces a more intense activation of A-delta nociceptors that occurs after a shorter onset latency compared with the activation of C-fibre nociceptors. Thus, in direct challenge to the traditional model of FRO, a shift in the dose-response relationship of morphine to the right with a reduction in efficacy, may reflect the limited effectiveness of morphine to attenuate the A-delta-mediated component which assumes increasing dominance at high intensity heating. In our appraisal of other nociceptive models we provide an in-depth characterization of afferent processing in the early neonate rat, in which opioids have been tested in both phasic (tail flick and hot-plate) and tonic (formalin) tests. Afferent processing in this model is typified by several behavioural, anatomical and functional features which, although not pathological, are characteristic of those observed in models of nerve injury using the adult rat. Notably, these features include a lack of segmental inhibition ('disinhibition') and afferent input in large diameter myelinated fibres which make synaptic contacts within superficial laminae of the dorsal horn that in the adult are predominantly nociceptive. Paradoxically, because this paradigm demonstrates increased sensitivity to the antinociceptive effects of opioids it may have special merit as a model of tonic pain. It was recently announced that the i.t. administration of pertussis toxin (PTX) caused hyperalgesia and allodynia that appears similar to the symptoms reported by patients suffering from neuropathic pain. Unlike the effects of other opioids so far tested, buprenorphine-induced antinociception is not blocked in this model. This is an exciting finding and provides new optimism that some opioids, notably buprenorphine, may have a special role in managing some types of neuropathic pain.
Pain 1998 Nov
PMID:Some new insights into the effects of opioids in phasic and tonic nociceptive tests. 983 18


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