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Objective: The present study was designed to observe the effect of different frequencies of EAS on the expression of hippocampal muscarinic and nicotinic acetylcholinergic receptors (mAChRs, nAChRs) in neuropathic pain rats for revealing their relationship.Methods:Forty male Wistar rats were randomly and equally divided into sham, model, 2Hz, 2Hz/15Hz and 100Hz EAS groups (n=8/group).Neuropathic pain model was established by ligature of the left sciatic nerve to induce chronic constriction injury (CCI).EAS was applied to bilateral Zusanli (ST36)-Yanglingquan (GB34) 30min, once daily for 14 days.The mechanical pain thresholds (withdrawal latencies, PWLs) of hindpaws were detected.The expression levels of hippocampal M 1 and M2 mAChR, and α-4 and β-2 nAChR genes and proteins were detected by quantitative RT-PCR and Western blot, separately.Results: Following 2Hz, 2Hz/15Hz and 100Hz EAS, the CCI-induced increase of difference values of bilateral PWLs on day 6 and 14 was significantly down-regulated (P<0.05), with the 2Hz/15Hz being notably better than 100Hz EAS on day 14 (P<0.05).No significant difference was found between 2Hz and 2Hz/15Hz EAs in the PWL difference (P>0.05), suggesting a better analgesic action of 2Hz and 2Hz/15Hz EAS.After 2 weeks EA intervention, the decreased expression levels of M 1 mAChR mRNA of both 2Hz and 2/15Hz groups and M1 mAChR protein of the three EAS groups, α-4 AChR rnRNA of the 2Hz/15Hz group and β-2 nAChR protein of the three EAS groups were considerably increased (P<0.05), suggesting an involvement of M1 mAChR and β-2 nAChR proteins in EAS-induced pain relief in neuropathic pain rats.No significant changes were found in the expression of M2 mAChR rnRNA and protein, α-4 nAChR protein and β-2 nAChR mRNA after CCI and EAS (P>0.05).Conclusion: EAS of ST36-GB34 at 2Hz and 2Hz/15Hz has a better analgesic effect in neuropathic pain rats, which is probably associated with its effects in upregulating expression of hippocampal M 1 mAChR mRNA and protein and β-2 nAChR protein.