Low frequency electroacupuncture alleviates neuropathic pain by activation of spinal microglial IL-10/ß-endorphin pathway.
Biomed Pharmacother
; 125: 109898, 2020 May.
Article
em En
| MEDLINE
| ID: mdl-32004977
ABSTRACT
Electroacupuncture produces analgesia in chronic pain patients and animal models of pain hypersensitivity. The current study aims to illustrate the mechanisms underlying electroacupuncture-attenuated neuropathic pain. Neuropathic rats, induced by tight ligation of L5/L6 spinal nerves, markedly reduced mechanical thresholds in the ipsilateral hindpaws relative to the contralateral hindpaws. Low frequency (2 Hz) electroacupuncture stimulation for a period of 20 min alleviated neuropathic pain in the ipsilateral hindpaws of neuropathic rats in a time-dependent manner. The same electroacupuncture treatment also stimulated spinal gene and protein expression of IL-10 and ß-endorphin but not dynorphin A, measured by real-time quantitative PCR and ELISA kits. Intrathecal injection of the specific IL-10 antibody in neuropathic rats completely blocked electroacupuncture-increased spinal expression of ß-endorphin, but the ß-endorphin antibody failed to alter electroacupuncture-stimulated spinal IL-10 expression. Using a double fluorescence immunostaining technique, we observed that electroacupuncture stimulated spinal IL-10 and ß-endorphin expression in microglia but not in neurons or astrocytes in the spinal dorsal horn of neuropathic rats. Pretreatment with intrathecal injection of the microglial inhibitor minocycline, specific IL-10 antibody and ß-endorphin antiserum (but not the dynorphin A antibody), or selective µ-opioid receptor antagonist CTAP (but not κ- or δ-opioid receptor antagonist) completely blocked electroacupuncture-induced attenuation of neuropathic pain. These results suggest that low frequency electroacupuncture alleviates neuropathic pain through stimulation of the spinal microglial expression of IL-10 and subsequent expression of ß-endorphin.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Beta-Endorfina
/
Eletroacupuntura
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Interleucina-10
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Microglia
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Neuralgia
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Biomed Pharmacother
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
China