Xue J I, Yu Y X, Han J S, Jen M F
Neuroscience Research Center, Beijing Medical University, China.
Int J Neurosci. 1995 May;82(1-2):95-104. doi: 10.3109/00207459508994293.
Previous study in our group demonstrated that dynorphin exerted a significant analgesic effect in spinal cord, and electroacupuncture (EA) of high frequency (100 Hz) produced analgesia which was mediated by dynorphin released in spinal cord. However, no data are up to nowadays available for demonstrating either from anterior horn or from dorsal horn the dynorphin comes. Using radioimmunoassay, we found in the present study that ir-dynorphin content in dorsal horn was 10 times more than in anterior horn, which were 11.24 +/- 0.91 pmol/10 mg protein and 1.08 +/- 0.20 pmol/10 mg protein, respectively. Stimulation of 100 Hz EA for 30 min produced a significant increase of ir-dynorphin content in dorsal horn, in contrast, no change of ir-dynorphin content was found in anterior horn. For the meanwhile, a significant elevation of ir-dynorphin was induced by 100 Hz EA in cerebrospinal fluid. It is concluded according to these data that EA, as a stimulation in physiological condition, elevates the content of ir-dynorphin only in dorsal horn, and induces release of dynorphin in loci. The released dynorphin acts on dorsal horn to mediate the analgesia of EA.
我们小组之前的研究表明，强啡肽在脊髓中发挥显著的镇痛作用，高频（100Hz）电针（EA）产生的镇痛作用是由脊髓中释放的强啡肽介导的。然而，迄今为止，尚无数据表明强啡肽来自前角还是后角。在本研究中，我们使用放射免疫分析法发现，后角中免疫反应性强啡肽（ir-强啡肽）的含量比前角高10倍，分别为11.24±0.91pmol/10mg蛋白质和1.08±0.20pmol/10mg蛋白质。100Hz电针刺激30分钟可使后角中ir-强啡肽含量显著增加，相比之下，前角中ir-强啡肽含量未发现变化。同时，100Hz电针可使脑脊液中ir-强啡肽显著升高。根据这些数据得出结论，电针作为一种生理条件下的刺激，仅在后角中升高ir-强啡肽的含量，并诱导强啡肽在局部释放。释放的强啡肽作用于后角以介导电针的镇痛作用。
