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1.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1484789

Resumo

Abstract Background: Spider venoms induce different physio-pharmacological effects by binding with high affinity on molecular targets, therefore being of biotechnological interest. Some of these toxins, acting on different types of ion channels, have been identified in the venom of spiders of the genus Phoneutria, mainly from P. nigriventer. In spite of the pharmaceutical potential demonstrated by P. nigriventer toxins, there is limited information on molecules from venoms of the same genus, as their toxins remain poorly characterized. Understanding this diversity and clarifying the differences in the mechanisms of action of spider toxins is of great importance for establishing their true biotechnological potential. This prompted us to compare three different venoms of the Phoneutria genus: P. nigriventer (Pn-V), P. eickstedtae (Pe-V) and P. pertyi (Pp-V). Methods: Biochemical and functional comparison of the venoms were carried out by SDS-PAGE, HPLC, mass spectrometry, enzymatic activities and electrophysiological assays (whole-cell patch clamp). Results: The employed approach revealed that all three venoms had an overall similarity in their components, with only minor differences. The presence of a high number of similar proteins was evident, particularly toxins in the mass range of ~6.0 kDa. Hyaluronidase and proteolytic activities were detected in all venoms, in addition to isoforms of the toxins Tx1 and Tx2-6. All Tx1 isoforms blocked Nav1.6 ion currents, with slight differences. Conclusion: Our findings showed that Pn-V, Pe-V and Pp-V are highly similar concerning protein composition and enzymatic activities, containing isoforms of the same toxins sharing high sequence homology, with minor modifications. However, these structural and functional variations are very important for venom diversity. In addition, our findings will contribute to the comprehension of the molecular diversity of the venoms of the other species from Phoneutria genus, exposing their biotechnological potential as a source for searching for new active molecules.

2.
J. venom. anim. toxins incl. trop. dis ; 28: e20210042, 2022. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360568

Resumo

Spider venoms induce different physio-pharmacological effects by binding with high affinity on molecular targets, therefore being of biotechnological interest. Some of these toxins, acting on different types of ion channels, have been identified in the venom of spiders of the genus Phoneutria, mainly from P. nigriventer. In spite of the pharmaceutical potential demonstrated by P. nigriventer toxins, there is limited information on molecules from venoms of the same genus, as their toxins remain poorly characterized. Understanding this diversity and clarifying the differences in the mechanisms of action of spider toxins is of great importance for establishing their true biotechnological potential. This prompted us to compare three different venoms of the Phoneutria genus: P. nigriventer (Pn-V), P. eickstedtae (Pe-V) and P. pertyi (Pp-V). Methods: Biochemical and functional comparison of the venoms were carried out by SDS-PAGE, HPLC, mass spectrometry, enzymatic activities and electrophysiological assays (whole-cell patch clamp). Results: The employed approach revealed that all three venoms had an overall similarity in their components, with only minor differences. The presence of a high number of similar proteins was evident, particularly toxins in the mass range of ~6.0 kDa. Hyaluronidase and proteolytic activities were detected in all venoms, in addition to isoforms of the toxins Tx1 and Tx2-6. All Tx1 isoforms blocked Nav1.6 ion currents, with slight differences. Conclusion: Our findings showed that Pn-V, Pe-V and Pp-V are highly similar concerning protein composition and enzymatic activities, containing isoforms of the same toxins sharing high sequence homology, with minor modifications. However, these structural and functional variations are very important for venom diversity. In addition, our findings will contribute to the comprehension of the molecular diversity of the venoms of the other species from Phoneutria genus, exposing their biotechnological potential as a source for searching for new active molecules.(AU)


Assuntos
Animais , Espectrometria de Massas/instrumentação , Venenos de Aranha/análise , Aranhas , Isoformas de Proteínas/biossíntese , Hialuronoglucosaminidase , Preparações Farmacêuticas
3.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1484780

Resumo

Abstract Background: Phoneutria nigriventer venom contains Ph1. This toxin and its recombinant form have a remarkable analgesic potential that is associated with blockage of voltage-gated calcium channels and TRPA1 receptors. Although morphine is a mainstay drug to treat moderate and severe pain related to cancer, it has serious and dose-limiting side effects. Combining recombinant Ph1 and morphine to treat pain is an interesting approach that has been gaining attention. Therefore, a quantitative and reliable method to establish the strength of the antinociceptive interaction between these two substances is necessary. The present study was designed to investigate the nature of the functional antinociceptive (analgesic) interaction between Ph1 recombinant toxin and morphine in a model of cancer pain. Methods: Melanoma was produced by intraplantar inoculation of B16-F10 cells into the right paw of C57BL/6J mice. Von Frey filaments measured the paw-withdrawal threshold after intrathecal administration of morphine, recombinant Ph1, and their combination. Thermal hyperalgesia was assessed using Hargreaves apparatus. The degree of interaction was evaluated using isobolographic analysis. Spontaneous and forced motor performance was assessed with the open-field and rotarod tests, respectively. Results: Co-administration of recombinant Ph1 and morphine synergistically reverses the melanoma-induced mechanical hyperalgesia. The potency of the mixture, measured as the effective dose to reach 50% of maximum possible effect (MPE) in ameliorating mechanical hyperalgesia, was about twice fold higher than expected if the interaction between morphine and recombinant Ph1 was merely additive. Treatment with the combination at doses necessary to reach 50% of MPE caused no spontaneous nor forced motor alterations. Conclusion: The combinatorial use of recombinant Ph1 and morphine allows significant and effective dose reduction of both agents, which has translational potential for opioid-sparing approaches in pain management related to cancer.

4.
J. venom. anim. toxins incl. trop. dis ; 27: e20210027, 2021. ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1395714

Resumo

Background: Phoneutria nigriventer venom contains Phα1ß. This toxin and its recombinant form have a remarkable analgesic potential that is associated with blockage of voltage-gated calcium channels and TRPA1 receptors. Although morphine is a mainstay drug to treat moderate and severe pain related to cancer, it has serious and dose-limiting side effects. Combining recombinant Phα1ß and morphine to treat pain is an interesting approach that has been gaining attention. Therefore, a quantitative and reliable method to establish the strength of the antinociceptive interaction between these two substances is necessary. The present study was designed to investigate the nature of the functional antinociceptive (analgesic) interaction between Phα1ß recombinant toxin and morphine in a model of cancer pain. Methods: Melanoma was produced by intraplantar inoculation of B16-F10 cells into the right paw of C57BL/6J mice. Von Frey filaments measured the paw-withdrawal threshold after intrathecal administration of morphine, recombinant Phα1ß, and their combination. Thermal hyperalgesia was assessed using Hargreaves apparatus. The degree of interaction was evaluated using isobolographic analysis. Spontaneous and forced motor performance was assessed with the open-field and rotarod tests, respectively. Results: Co-administration of recombinant Phα1ß and morphine synergistically reverses the melanoma-induced mechanical hyperalgesia. The potency of the mixture, measured as the effective dose to reach 50% of maximum possible effect (MPE) in ameliorating mechanical hyperalgesia, was about twice fold higher than expected if the interaction between morphine and recombinant Phα1ß was merely additive. Treatment with the combination at doses necessary to reach 50% of MPE caused no spontaneous nor forced motor alterations. Conclusion: The combinatorial use of recombinant Phα1ß and morphine allows significant and effective dose reduction of both agents, which has translational potential for opioid-sparing approaches in pain management related to cancer.(AU)


Assuntos
Animais , Fenômenos Biológicos/efeitos dos fármacos , Dor do Câncer/veterinária , Analgésicos/efeitos adversos , Proteínas Recombinantes/toxicidade , Camundongos/fisiologia , Morfina/análise
5.
J. venom. anim. toxins incl. trop. dis ; 26: e20190075, 2020. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1101266

Resumo

Phoneutria nigriventer spider venom contains several cysteine-rich peptide toxins that act on different ion channels. Despite extensive studies on its venom and description of cDNA sequences of several of its toxin precursors, the gene structure of these toxins remains unknown. Methods: Genomic regions encoding the precursors of three previously characterized P. nigriventer toxins - PnTx1, PnTx2-5 and PnTx4(5-5) - were amplified by PCR using specific primers. PCR fragments were cloned and sequenced. Obtained sequences were compared with their corresponding cDNA sequences. Results: The size of PCR fragments obtained and sequences corresponding to genomic regions encoding for the toxin precursors matched their cDNA sequences. Conclusions: Despite a few nucleotide substitutions in the genomic regions encoding for the toxin precursors when compared with cDNA sequences, the results of the present work indicate that P. nigriventer toxins do not contain introns in their genes sequences.(AU)


Assuntos
Animais , Venenos de Aranha , Íntrons , Reação em Cadeia da Polimerase , Análise de Sequência , Cisteína , Nucleotídeos
6.
J. venom. anim. toxins incl. trop. dis ; 26: e20200031, 2020. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1135135

Resumo

PnPa11 and PnPa13 are synthetic peptides derived from Phoneutria nigriventer spider venom, which display antinociceptive and neuroprotective properties. In this work, we evaluated the safety of intravitreal use and the neuroprotective effect of these peptides. Methods: The cytotoxicity and the antiangiogenic activity of these peptides were evaluated by the sulforhodamine-B method and chicken chorioallantoic membrane (CAM) assay, respectively. The in vivo safety was analyzed in Wistar rats that were intravitreally injected with different doses (0.50; 1.25; 2.50; 3.75 and 5.00 µg/mL) of these peptides (right eye, n = 6). The retinal function was assessed by electroretinography exams (ERG), intraocular pressure (IOP), and histological analyzes. In order to investigate the neuroprotective effect, Wistar rats received intravitreal injections (right eye, n = 6) of peptides at 1.25 µg/mL and then were exposed to blue LED light. In addition, the visual function and the retinal microstructure were verified. Results: Cytotoxicity analyses demonstrated that the peptides did not present any toxicity over ARPE-19 (adult retinal pigmented epithelial) cell line and the antiangiogenic study highlighted that the peptides promoted the reduction of blood vessels. The intravitreal injection did not cause major changes, neither induced any irreversible damage. In the retinal degeneration assay, the ERG records demonstrated that the prior treatment with PnPa11 and PnPa13 protected the retina from damage. Morphological analyses confirmed the ERG findings. Immunoblotting analyses revealed that PnPa11 increased Erk1/2, NR2A, and NR2B retinal expression after the light stress model, but did not cause Akt1 activation, while PnPa13 prevented Erk1/2 and Akt1 dephosphorylation. Conclusions: The intraocular administration of these peptides was well tolerated and presented protective activity against retinal degeneration, suggesting the potential use of these peptides as neuroprotectors in the ophthalmological field.(AU)


Assuntos
Animais , Peptídeos , Venenos de Aranha , Injeções Intravítreas , Aranhas , Analgésicos
7.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 26: e20200031, 2020. graf
Artigo em Inglês | VETINDEX | ID: vti-32333

Resumo

PnPa11 and PnPa13 are synthetic peptides derived from Phoneutria nigriventer spider venom, which display antinociceptive and neuroprotective properties. In this work, we evaluated the safety of intravitreal use and the neuroprotective effect of these peptides. Methods: The cytotoxicity and the antiangiogenic activity of these peptides were evaluated by the sulforhodamine-B method and chicken chorioallantoic membrane (CAM) assay, respectively. The in vivo safety was analyzed in Wistar rats that were intravitreally injected with different doses (0.50; 1.25; 2.50; 3.75 and 5.00 µg/mL) of these peptides (right eye, n = 6). The retinal function was assessed by electroretinography exams (ERG), intraocular pressure (IOP), and histological analyzes. In order to investigate the neuroprotective effect, Wistar rats received intravitreal injections (right eye, n = 6) of peptides at 1.25 µg/mL and then were exposed to blue LED light. In addition, the visual function and the retinal microstructure were verified. Results: Cytotoxicity analyses demonstrated that the peptides did not present any toxicity over ARPE-19 (adult retinal pigmented epithelial) cell line and the antiangiogenic study highlighted that the peptides promoted the reduction of blood vessels. The intravitreal injection did not cause major changes, neither induced any irreversible damage. In the retinal degeneration assay, the ERG records demonstrated that the prior treatment with PnPa11 and PnPa13 protected the retina from damage. Morphological analyses confirmed the ERG findings. Immunoblotting analyses revealed that PnPa11 increased Erk1/2, NR2A, and NR2B retinal expression after the light stress model, but did not cause Akt1 activation, while PnPa13 prevented Erk1/2 and Akt1 dephosphorylation. Conclusions: The intraocular administration of these peptides was well tolerated and presented protective activity against retinal degeneration, suggesting the potential use of these peptides as neuroprotectors in the ophthalmological field.(AU)


Assuntos
Animais , Aranhas/química , Injeções Intravítreas/métodos , Peptídeos/análise , Peptídeos/química , Neuroproteção , Doenças Retinianas
8.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 26: e20190075, Apr. 30, 2020. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-29961

Resumo

Background: Phoneutria nigriventer spider venom contains several cysteine-rich peptide toxins that act on different ion channels. Despite extensive studies on its venom and description of cDNA sequences of several of its toxin precursors, the gene structure of these toxins remains unknown. Methods: Genomic regions encoding the precursors of three previously characterized P. nigriventer toxins - PnTx1, PnTx2-5 and PnTx4(5-5) - were amplified by PCR using specific primers. PCR fragments were cloned and sequenced. Obtained sequences were compared with their corresponding cDNA sequences. Results: The size of PCR fragments obtained and sequences corresponding to genomic regions encoding for the toxin precursors matched their cDNA sequences. Conclusions: Despite a few nucleotide substitutions in the genomic regions encoding for the toxin precursors when compared with cDNA sequences, the results of the present work indicate that P. nigriventer toxins do not contain introns in their genes sequences.(AU)


Assuntos
Animais , Venenos de Aranha/genética , Venenos de Aranha/isolamento & purificação , Toxinas Biológicas/isolamento & purificação , Íntrons , Toxinas Biológicas/genética , Aranhas
9.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 25: e20190022, Aug. 12, 2019. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-21885

Resumo

Background:The venom of Phoneutria nigriventer spider is a source of numerous bioactive substances, including some toxins active in insects. An example is PnTx4(5-5) that shows a high insecticidal activity and no apparent toxicity to mice, although it inhibited NMDA-evoked currents in rat hippocampal neurons. In this work the analgesic activity of PnTx4(5-5) (renamed Γ-ctenitoxin-Pn1a) was investigated.Methods:The antinociceptive activity was evaluated using the paw pressure test in rats, after hyperalgesia induction with intraplantar injection of carrageenan or prostaglandin E2 (PGE2).Results:PnTx4(5-5), subcutaneously injected, was able to reduce the hyperalgesia induced by PGE2 in rat paw, demonstrating a systemic effect. PnTx4(5-5) administered in the plantar surface of the paw caused a peripheral and dose-dependent antinociceptive effect on hyperalgesia induced by carrageenan or PGE2. The hyperalgesic effect observed in these two pain models was completely reversed with 5 µg of PnTx4(5-5). Intraplantar administration of L-glutamate induced hyperalgesic effect that was significantly reverted by 5 μg of PnTx4(5-5) injection in rat paw.Conclusion:The antinociceptive effect for PnTx4(5-5) was demonstrated against different rat pain models, i.e. induced by PGE2, carrageenan or glutamate. We suggest that the antinociceptive effect of PnTx4(5-5) may be related to an inhibitory activity on the glutamatergic system.(AU)


Assuntos
Animais , Ratos , Nociceptividade , Analgésicos/análise , Peptídeos , Venenos de Aranha/uso terapêutico , Glutamatos
10.
J. venom. anim. toxins incl. trop. dis ; 25: e20190022, 2019. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1012634

Resumo

The venom of Phoneutria nigriventer spider is a source of numerous bioactive substances, including some toxins active in insects. An example is PnTx4(5-5) that shows a high insecticidal activity and no apparent toxicity to mice, although it inhibited NMDA-evoked currents in rat hippocampal neurons. In this work the analgesic activity of PnTx4(5-5) (renamed Γ-ctenitoxin-Pn1a) was investigated. Methods: The antinociceptive activity was evaluated using the paw pressure test in rats, after hyperalgesia induction with intraplantar injection of carrageenan or prostaglandin E2 (PGE2). Results: PnTx4(5-5), subcutaneously injected, was able to reduce the hyperalgesia induced by PGE2 in rat paw, demonstrating a systemic effect. PnTx4(5-5) administered in the plantar surface of the paw caused a peripheral and dose-dependent antinociceptive effect on hyperalgesia induced by carrageenan or PGE2. The hyperalgesic effect observed in these two pain models was completely reversed with 5 µg of PnTx4(5-5). Intraplantar administration of L-glutamate induced hyperalgesic effect that was significantly reverted by 5 μg of PnTx4(5-5) injection in rat paw. Conclusion: The antinociceptive effect for PnTx4(5-5) was demonstrated against different rat pain models, i.e. induced by PGE2, carrageenan or glutamate. We suggest that the antinociceptive effect of PnTx4(5-5) may be related to an inhibitory activity on the glutamatergic system.(AU)


Assuntos
Venenos de Aranha , Dinoprostona , Fármacos Atuantes sobre Aminoácidos Excitatórios , Analgésicos/síntese química
11.
Tese em Português | VETTESES | ID: vtt-220140

Resumo

O filo Arthropoda compreende aproximadamente 85% das espécies animais já descritas. Dentro deste filo a classe Arachnida inclui invertebrados de grande importância, devido à transmissão de doenças e aos acidentes por envenenamento. Aranhas do gênero Phoneutria sp., popularmente conhecidas como aranha-amadeira, são aracnídeos de interesse médico pertencentes à família Ctenidae. Exemplares destas aranhas são recebidos, quarentenados e mantidos em cativeiro no Biotério de Artrópodes do Instituto Butantan, São Paulo, Brasil, com o objetivo de extrair o seu veneno para posterior produção do soro antiaracnídico. Foram analisadas em microscopia ótica, amostras de fezes de 509 Phoneutria nigriventer, destas, 131 (25,73%) apresentaram infecção por protozoários. As amostras positivas ao exame parasitológico foram submetidas a extração de DNA e reações de amplificação (PCR), resultando em 80 amplificadas, purificadas e sequenciadas. 17 sequências foram obtidas e analisadas por BLAST. Cinco amostras foram identificadas como Colpoda steinii, uma como Colpoda aspera, uma apenas pelo gênero Colpoda sp. e uma identificada como organismo ciliado. Quatro amostras foram identificadas como Parabodo caudatus, duas como Urostipulosphaera sp., uma como Helkesimastix sp. e uma como um protozoário euglenóide. Uma amostra sequenciada foi identificada como uma alga pertencente ao gênero Laurencia sp. A presença de sinais clínicos e outros eventos foram observados em 17 aranhas, e então associados ao resultado do sequenciamento.


The phylum Arthropoda comprises approximately 85% of the described animal species. Within this phylum, the class Arachnida comprises some invertebrates of great importance, due to the transmission of diseases and to the risk of human envenomation. Spiders belonging to the genus Phoneutria sp., popularly known as armed-spiders, are arachnids of medical importance of the Ctenidae family. These animals are received, quarantined and maintained in captivity at the Biotério de Artrópodes of the Instituto Butantan, São Paulo, Brazil, with the aim to extract its venom for the production of the anti-arachnid serum. 509 Phoneutria nigriventer feaces samples were analyzed in optical microscopy, being 131 (25.73%) positive for protozoan. The positive samples were subjected to DNA extraction and amplification reactions (PCR), where 80 samples were amplified, purified and sequenced. 17 sequences were obtained and analyzed by BLAST. Five sequences were identified as Colpoda steiini, one as Colpoda aspera, one belonging to the genus Colpoda sp. and one as ciliated organism. Four sequences were identified as Parabodo caudatus, two as Urostipulosphaera sp., one as Helkesimastix sp. and one as a Euglena-like protozoan. One sequenced sample was identified as an algae belonging to the genus Laurencia sp. The presence of clinical signs and other events was observed in 17 spiders, and then associated with the sequencing results.

12.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954801

Resumo

Background: Some peptides purified from the venom of the spider Phoneutria nigriventer have been identified as potential sources of drugs for pain treatment. In this study, we characterized the antinociceptive effect of the peptide PnPP-19 on the central nervous system and investigated the possible involvement of opioid and cannabinoid systems in its action mechanism. Methods: Nociceptive threshold to thermal stimulation was measured according to the tail-flick test in Swiss mice. All drugs were administered by the intracerebroventricular route.Results: PnPP-19 induced central antinociception in mice in the doses of 0.5 and 1 µg. The non-selective opioid receptor antagonist naloxone (2.5 and 5 µg), µ-opioid receptor antagonist clocinnamox (2 and 4 µg), δ-opioid receptor antagonist naltrindole (6 and 12 µg) and CB1 receptor antagonist AM251 (2 and 4 µg) partially inhibited the antinociceptive effect of PnPP-19 (1 µg). Additionally, the anandamide amidase inhibitor MAFP (0.2 µg), the anandamide uptake inhibitor VDM11 (4 µg) and the aminopeptidase inhibitor bestatin (20 µg) significantly enhanced the antinociception induced by a low dose of PnPP-19 (0.5 µg). In contrast, the κ-opioid receptor antagonist nor-binaltorphimine (10 µg and 20 µg) and the CB2 receptor antagonist AM630 (2 and 4 µg) do not appear to be involved in this effect. Conclusions: PnPP-19-induced central antinociception involves the activation of CB1 cannabinoid, µ- and δ-opioid receptors. Mobilization of endogenous opioids and cannabinoids might be required for the activation of those receptors, since inhibitors of endogenous substances potentiate the effect of PnPP-19. Our results contribute to elucidating the action of the peptide PnPP-19 in the antinociceptive pathway.(AU)


Assuntos
Animais , Peptídeos , Aranhas , Canabinoides , Sistema Nervoso Central , Analgésicos Opioides , Receptor CB1 de Canabinoide , Receptor CB2 de Canabinoide
13.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 22: [1-7], Janeiro 19, 2016. graf
Artigo em Inglês | VETINDEX | ID: vti-16028

Resumo

Some peptides purified from the venom of the spider Phoneutria nigriventer have been identified as potential sources of drugs for pain treatment. In this study, we characterized the antinociceptive effect of the peptide PnPP-19 on the central nervous system and investigated the possible involvement of opioid and cannabinoid systems in its action mechanism. Methods Nociceptive threshold to thermal stimulation was measured according to the tail-flick test in Swiss mice. All drugs were administered by the intracerebroventricular route. Results PnPP-19 induced central antinociception in mice in the doses of 0.5 and 1 g. The non-selective opioid receptor antagonist naloxone (2.5 and 5 g), -opioid receptor antagonist clocinnamox (2 and 4 g), -opioid receptor antagonist naltrindole (6 and 12 g) and CB1 receptor antagonist AM251 (2 and 4 g) partially inhibited the antinociceptive effect of PnPP-19 (1 g). Additionally, the anandamide amidase inhibitor MAFP (0.2 g), the anandamide uptake inhibitor VDM11 (4 g) and the aminopeptidase inhibitor bestatin (20 g) significantly enhanced the antinociception induced by a low dose of PnPP-19 (0.5 g). In contrast, the -opioid receptor antagonist nor-binaltorphimine (10 g and 20 g) and the CB2 receptor antagonist AM630 (2 and 4 g) do not appear to be involved in this effect. Conclusions PnPP-19-induced central antinociception involves the activation of CB1 cannabinoid, - and -opioid receptors. Mobilization of endogenous opioids and cannabinoids might be required for the activation of those receptors, since inhibitors of endogenous substances potentiate the effect of PnPP-19. Our results contribute to elucidating the action of the peptide PnPP-19 in the antinociceptive pathway.(AU)


Assuntos
Animais , Aranhas/química , Analgésicos/administração & dosagem , Analgésicos/química , Analgésicos/síntese química , Peptídeos/síntese química
14.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484657

Resumo

Some peptides purified from the venom of the spider Phoneutria nigriventer have been identified as potential sources of drugs for pain treatment. In this study, we characterized the antinociceptive effect of the peptide PnPP-19 on the central nervous system and investigated the possible involvement of opioid and cannabinoid systems in its action mechanism. Methods Nociceptive threshold to thermal stimulation was measured according to the tail-flick test in Swiss mice. All drugs were administered by the intracerebroventricular route. Results PnPP-19 induced central antinociception in mice in the doses of 0.5 and 1 g. The non-selective opioid receptor antagonist naloxone (2.5 and 5 g), -opioid receptor antagonist clocinnamox (2 and 4 g), -opioid receptor antagonist naltrindole (6 and 12 g) and CB1 receptor antagonist AM251 (2 and 4 g) partially inhibited the antinociceptive effect of PnPP-19 (1 g). Additionally, the anandamide amidase inhibitor MAFP (0.2 g), the anandamide uptake inhibitor VDM11 (4 g) and the aminopeptidase inhibitor bestatin (20 g) significantly enhanced the antinociception induced by a low dose of PnPP-19 (0.5 g). In contrast, the -opioid receptor antagonist nor-binaltorphimine (10 g and 20 g) and the CB2 receptor antagonist AM630 (2 and 4 g) do not appear to be involved in this effect. Conclusions PnPP-19-induced central antinociception involves the activation of CB1 cannabinoid, - and -opioid receptors. Mobilization of endogenous opioids and cannabinoids might be required for the activation of those receptors, since inhibitors of endogenous substances potentiate the effect of PnPP-19. Our results contribute to elucidating the action of the peptide PnPP-19 in the antinociceptive pathway.


Assuntos
Animais , Analgésicos/administração & dosagem , Analgésicos/química , Analgésicos/síntese química , Aranhas/química , Peptídeos/síntese química
15.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954733

Resumo

The article provides a historical report on venomous spider identification, venom obtainment methods and serum production at the Butantan Institute, São Paulo, Brazil. It is based on literature and personnal experience during the last 50 years. This result is the discovery that the real species causing potential severe human accidents were the spiders of the genus Loxosceles and Phoneutria.(AU)


Assuntos
Animais , Aranhas , Antivenenos , História , Relatório de Pesquisa
16.
Artigo em Inglês | VETINDEX | ID: vti-27383

Resumo

The article provides a historical report on venomous spider identification, venom obtainment methods and serum production at the Butantan Institute, São Paulo, Brazil. It is based on literature and personnal experience during the last 50 years. This result is the discovery that the real species causing potential severe human accidents were the spiders of the genus Loxosceles and Phoneutria.(AU)


Assuntos
Animais , Venenos de Aranha/análise , Venenos de Aranha/história , Animais Peçonhentos , Antivenenos
17.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484610

Resumo

The article provides a historical report on venomous spider identification, venom obtainment methods and serum production at the Butantan Institute, São Paulo, Brazil. It is based on literature and personnal experience during the last 50 years. This result is the discovery that the real species causing potential severe human accidents were the spiders of the genus Loxosceles and Phoneutria.


Assuntos
Animais , Animais Peçonhentos , Antivenenos , Venenos de Aranha/análise , Venenos de Aranha/história
18.
Cad. técn. Vet. Zoot. ; (75): 63-72, dez. 2014. tab, ilus
Artigo em Português | VETINDEX | ID: vti-481337

Resumo

Existem mais de 30 mil espécies de aranhas descritas no mundo, sendo agrande maioria peçonhenta. As aranhas de interesse veterinário no Brasil pertencem aos gêneros Loxosceles e Phoneutria.


Assuntos
Animais , Animais Peçonhentos/anormalidades , Animais Peçonhentos/fisiologia , /diagnóstico , Picada de Aranha/terapia , Aranhas/anatomia & histologia , Aranhas/fisiologia , Terapêutica , Peçonhas/efeitos adversos , Peçonhas/análise
19.
Cad. téc. vet. zootec ; (75): 63-72, dez. 2014. tab, ilus
Artigo em Português | VETINDEX | ID: biblio-1471480

Resumo

Existem mais de 30 mil espécies de aranhas descritas no mundo, sendo agrande maioria peçonhenta. As aranhas de interesse veterinário no Brasil pertencem aos gêneros Loxosceles e Phoneutria.


Assuntos
Animais , Animais Peçonhentos/anormalidades , Animais Peçonhentos/fisiologia , Aranhas/anatomia & histologia , Aranhas/fisiologia , Picada de Aranha/terapia , Peçonhas/análise , Peçonhas/efeitos adversos , Terapêutica
20.
Vet. foco ; 9(2)2012.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1502829

Resumo

Os acidentes causados por aranhas são frequentes em nosso meio. A Phoneutria sp. é conhecida popularmente por aranha-armadeira e considerada a mais perigosa do Brasil. Estas aranhas são responsabilizadas pelo maior número de acidentes aracnídeos notificados ao Ministério da Saúde. Foi atendido no Hospital de Clínicas Veterinária da Universidade Federaldo Rio Grande do Sul (HCV-UFRGS) um canino, cocker spaniel, 11 meses de idade, picado por aranha do gênero Phoneutria sp., que foi internado e submetido às terapias necessárias. O animal apresentando sinais clínicos de acidente aracnídico de grau grave, pela indisponibilidade, não recebeu o soro antiaracnídico, indo a óbito por choque neurogênico.

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