The analgesic effect of crotoxin on neuropathic pain is mediated by central muscarinic receptors and 5-lipoxygenase-derived mediators.
Pharmacol Biochem Behav
; 91(2): 252-60, 2008 Dec.
Article
em En
| MEDLINE
| ID: mdl-18778727
Crotoxin (CTX), a neurotoxin isolated from the venom of the South American rattlesnake Crotalus durissus terrificus, induces analgesia. In this study, we evaluated the antinociceptive effect of CTX in a model of neuropathic pain induced by rat sciatic nerve transection. Hyperalgesia was detected 2 h after nerve transection and persisted for 64 days. Immersion of proximal and distal nerve stumps in CTX solution (0.01 mM for 10 s), immediately after nerve transection, blocked hyperalgesia. The antinociceptive effect of CTX was long-lasting, since it was detected 2 h after treatment and persisted for 64 days. CTX also delayed, but did not block, neurectomy-induced neuroma formation. The effect of CTX was blocked by zileuton (100 mg/kg, p.o.) and atropine (10 mg/kg, i.p.), and reduced by yohimbine (2 mg/kg, i.p.) and methysergide (5 mg/kg, i.p.). On the other hand, indomethacin (4 mg/kg, i.v.), naloxone (1 mg/kg, i.p.), and N-methyl atropine (30 mg/kg, i.p.) did not interfere with the effect of CTX. These results indicate that CTX induces a long-lasting antinociceptive effect in neuropathic pain, which is mediated by activation of central muscarinic receptors and partially, by activation of alpha-adrenoceptors and 5-HT receptors. Eicosanoids derived from the lipoxygenase pathway modulate the action of crotoxin.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Dor
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Araquidonato 5-Lipoxigenase
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Receptores Muscarínicos
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Doenças do Sistema Nervoso Periférico
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Analgésicos não Narcóticos
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Crotoxina
Limite:
Animals
Idioma:
En
Revista:
Pharmacol Biochem Behav
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Estados Unidos