[Effects of electroacupuncture at different acupoints on the pain behavior and NMDA receptor 2 B subunit mRNA and protein expression and phosphorylation level in the cervical spinal cord in rats with thyroid regional pain].
Zhen Ci Yan Jiu. 2009 Dec; 34(6):376-82.ZC

Abstract

OBJECTIVE

To observe the effect of electroacupuncture (EA) of different acupoint groups on the expression of NR 2 B subunit of N-methyl-D-aspartate (NMDA) receptor in the cervical spinal cord in rats with thyroid regional pain so as to analyze the analgesic mechanism of acupuncture for performing thyroid surgery.

METHODS

A total of 50 Wistar rats were randomized into control, model, EA-Futu (ST 32), EA-Hegu (LI 4)-Neiguan (PC 6, EA-LI 4-PC 6), EA-Zusanli (ST 36)-Yanglingquan (GB 34, EA-ST 36-GB 34) groups, with 10 cases in each. Thyroid regional pain model was established by subcutaneous injection of 2.5% formaldehyde. Ten minutes after modeling, EA (2 Hz/100 Hz, 1 mA) was applied to ST 32, LI 4-PC 6 and ST 36-GB 34 for 30 min respectively. The animals' face-grooming (FG) times and paw withdrawal latency (PWL) of radiant heat irradiation were recorded. The spinal cord tissues of the cervical 1-3 segments were removed for detecting the expression of NR 2 B mRNA and protein of NMDA receptor with reversed transcription-polymerase chain reaction and Western blotting techniques separately.

RESULTS

After subcutaneous injection of 2.5% formaldehyde, the animals' FG times increased considerably and the PWL was shortened obviously (P<0.05). Compared with model group, the FG times of EA-ST 32 and EA-LI 4-PC 6 groups at 40-45 min and 70-75 min after modeling decreased significantly, and their PWL prolonged markedly (P<0.05). The effect of EA-ST 32 was apparently superior to that of EA-LI 4-PC 6 group in reducing FG times. No significant differences were found between EA-ST 32 and EA-LI 4-PC 6 groups in PWL, and between model and EA-ST 36-GB 34 groups (P>0.05). Results of NR 2 B mRNA and protein detections showed no significant differences among the 5 groups in their expression (P>0.05). Comparison of the phosphorylated NR 2 B among 5 groups showed that EA-ST 32 and EA-LI 4-PC 6 could effectively down-regulate 2.5% formaldehyde induced increase of NR 2 B phosphorylation levels (P<0.05), while EA-ST 36-GB 34 had no obvious effect on it (P>0.05).

CONCLUSION

Both EA-ST 32 and EA-LI 4-PC 6 can significantly suppress thyroid regional pain induced behavior reactions, which may be closely associated with their effects in down-regulating NR 2 B phosphorylated level. The analgesic effect of EA-ST 32 and EA-LI 4-PC 6 for thyroid surgery is relatively more effective in comparison with EA-ST 36-GB 34.

Authors+Show Affiliations

Gao YH
Institute of Acu-moxibustion, China Academy of Chinese Medical Sciences, Beijing 100700, China. gaoyonghui_2000@yahoo.com.cn
Chen SP
No affiliation info available
Wang JY
No affiliation info available
Qiao LN
No affiliation info available
Xu QL
No affiliation info available
Liu JL
No affiliation info available

MeSH

Acupuncture AnalgesiaAcupuncture PointsAnimalsCervical VertebraeElectroacupunctureGene ExpressionMalePainPain ManagementPhosphorylationRatsRats, WistarReceptors, N-Methyl-D-AspartateSpinal CordThyroid Diseases

Pub Type(s)

English Abstract
Journal Article
Research Support, Non-U.S. Gov't

Language

chi

PubMed ID

20209972