Acupuncture at the San Jiao meridian affects brain stem issue G protein content in a rat migraine model

Sue Wang; Wei Li; Guangwei Zhong; Zhenyan Li; Lingbo Wen

摘要：BACKGROUND: G protein is closely associated with vasomotion. Vasomotor dysfunction accompanies migraine attack. OBJECTIVE: To investigate the effects of the San Jiao meridian acupuncture on G protein content in a rat migraine model. DESIGN, TIME AND SETTING: The present randomized grouping, cellular and molecular biological level trial was performed at the Institute of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University & Key Laboratory for Tumor Proteomics of Ministry of Health between October 2003 and June 2004. MATERIALS: Forty healthy, male, Sprague Dawley rats were included in this study. The G6805-2A elector-acupuncture apparatus was a product of Shanghai Huayi Medical Instrument Factory, China. Nitroglycerin was produced by Guangzhou Mingxing Pharmaceutical Factory, China. Antibodies against inhibitory and stimulatory G proteins were purchased from Sigma Chemical Company, USA. METHODS: All 40 rats were randomly and evenly divided into 4 groups. In the blank control group, the rats remained untouched. Rats from the normal control group were subcutaneously administered 2 mL/kg physiological saline. In the model group, migraine was induced with a subcutaneous injection of 10 mg/kg nitroglycerin (5 g/L), and the rats received no further treatment. In the acupuncture-treated group, 30 minutes after migraine induction, acupuncture was performed at the bilateral Waiguan (SJ 5) and Yifeng (SJ 17) points, with an acupuncture depth of 1 mm. Electric-stimulation parameters of 20 Hz for low frequency, 40 Hz for high frequency, and 0.5-1.0 mA for current intensity were set. Ten acupuncture sessions were applied, with 20-minute low-frequency and 20-minute high-frequency stimulation and 3 seconds of interval time. MAIN OUTCOME MEASURES: Inhibitory and stimulatory G protein contents were detected by Western blot analysis. RESULTS: At 4 hours after migraine induction, compared with the blank control and normal control groups, stimulatory G protein concentration was significantly increased, while inhibitory G protein levels were significantly decreased in the model group (P < 0.01). In the acupuncture-treated group, both stimulatory and inhibitory G protein concentrations were significantly increased following acupuncture treatment (P < 0.01 ), but stimulatory G protein levels were less and the inhibitory G protein concentrations were greater compared to the model group (P < 0.01). There was no significant difference in stimulatory and inhibitory G protein levels between the blank control and normal control groups (P > 0.05). CONCLUSION: Dysfunctional G protein signal transductions in the rat brain stem may be responsible for migraine attack. Acupuncture at the San Jiao meridian ameliorates migraines by mediating the G protein signal transduction pathway.