电针疗法对臂丛根性撕脱伤脊髓后角及中央管nNOS蛋白表达的影响

Effect of electroacupuncture on the expression of neuronal nitric oxide synthase protein in the posterior horn of spinal cord and central canal of the root-avulsion injured

目的采用电针疗法干预大鼠臂丛神经撕脱伤模型，探索电针疗法对臂丛根性撕脱伤脊髓后角及中央管nNOS蛋白表达的影响。方法健康、雌性成年Sprague—Dawley（SD）大鼠共40只，行臂丛神经根性撕脱手术，随机分为撕脱伤组（AV组）和撕脱伤加电针治疗组（AV＋EA组），AV＋EA组动物隔日接受大椎（DU4）和手三里（L110）电针治疗直至处死，每次治疗的输出脉冲波形为非对称双向疏密波，以20Hz频率不间断治疗15min。动物存活1周、2周、3周、6周处死，选取C7节段脊髓，行NADPH-d酶组织化学染色和中性红复染。结果脊髓后角，在AV组nNOS的微量表达；在AV＋EA组2-3周nNOS在健侧的表达比伤侧增多，至6周脊髓后角nNOS阳性神经元表达AV组损伤侧；AV＋EA组nNOS阳性神经元的表达与同时期的AV组。结论电针疗法导致脊髓后角及中央管nNOS阳性神经元的时空表达特异性。

Objective In this study, the electroacupuncture therapy was performed to treat the rat model of BPRA in order to explore the effect of electroacupuncture therapy on the the expression of nNOS protein in the central canal and in the posterior horn of spinal cord. Methods Totally 40 female Sprague-Dawley （SD） rats were received brachial plexus roots （the 5th cervical-the 1st tho- racic） avulsion, then they were randomly divided into avulsion plus electro-acupuncture stimulation （AV＋EA） group and avulsion （AV） groups. The AV＋EA treated rats received a continuous 20 Hz asymmetric bidirectional disperse-dense wave at the acupuncture points （acupoints） of Dazhui （DU4） and Shousanli （LI10） for 15 minutes on every other day till the sacrifice of the animals, meanwhile the AV treated rats received no treatment. The animals were sacrificed after survived for 1, 2, 3 and 6 weeks, respectively. The cryostat sec- tions of the 7th cervical segments were prepared and carried with nicotinamide adenine dinucleotide phosphate diaphorase （NADPH- d） histochemistry stain and neutral red （NR） counter stain for every third sections. The number of nNOS-positive motoneurons in lesion side and survived motoneurons in both sides of the 7th cervical segments were counted blindly. The percentages of the nNOS-positive motoneurons were compared between different groups. Results In the posterior horn of spinal cord, in AV group, it was not related to the injury side and the control side. In AV＋EA group, there was no significant difference between two side, when come to the meta- phase （2-3 weeks）, the expression of nNOS in the control side increased, and at last, the expression of nNOS positive neurons in the posterior horn and of the spinal cord was almost disappeared. In the central canal, in the AV group, the injury side presents a peak that was expressed with the neuron damage, and the waveform changes with the death of neurons. The control side sustained a little ex- pression, and no changes were found. In the AV＋EA group, the early damage （lweek）, which tends to the injury side, the middle term （2-3 weeks）, nNOS most expresses in the control side, to the late injury （6week）, nNOS positive neurons in AV＋EA group and the same period of AV group. Conclusion After brachial plexus avulsion, nNOS is expressed in the posterior horn of the spinal cord and the central canal, and show the characteristics of different groups and time window have different expression. Electroacupuncture thera- py can cause the expression changes of nNOS in the spinal cord and the central canal in the different time and different region.