Thompson P A, Barohn R A, Krolick K A
Department of Microbiology, University of Texas Health Science Center, San Antonio 78284.
Muscle Nerve. 1992 Jan;15(1):94-100. doi: 10.1002/mus.880150116.
Two methods were compared with regard to their ability to detect acetylcholine receptor-dependent neuromuscular dysfunction in rats with experimental autoimmune myasthenia gravis. In both cases, detection of AChR impairment required amplification of symptoms by administration of the AChR antagonist curare and appeared to be directly related to increasing levels of circulating anti-AChR antibodies. First, in vivo evaluations of decremental compound motor action potentials following repetitive nerve stimulation were performed by electromyography. Impaired neuromuscular function (i.e., greater than 10% decrement) was noted only after rats had been immunized twice with AChR, requiring levels of circulating anti-AChR antibody greater than about 200 micrograms/mL in serum. In contrast, the direct in vitro evaluation of stimulated isometric twitch tension appeared to be more sensitive in that impaired AChR-dependent muscle contraction was clearly observed following a single AChR immunization, and, as shown previously, required anti-AChR antibody levels of about 50 micrograms/mL in serum. Further discussion is presented concerning the advantages and disadvantages associated with each method of monitoring disease.
比较了两种方法检测实验性自身免疫性重症肌无力大鼠中乙酰胆碱受体依赖性神经肌肉功能障碍的能力。在这两种情况下，检测乙酰胆碱受体损伤都需要通过给予乙酰胆碱受体拮抗剂箭毒来放大症状，并且似乎与循环抗乙酰胆碱受体抗体水平的升高直接相关。首先，通过肌电图对重复神经刺激后复合运动动作电位的递减进行体内评估。仅在大鼠用乙酰胆碱受体免疫两次后才观察到神经肌肉功能受损（即递减大于10%），这需要血清中循环抗乙酰胆碱受体抗体水平大于约200微克/毫升。相比之下，对刺激的等长抽搐张力的直接体外评估似乎更敏感，因为在单次乙酰胆碱受体免疫后就清楚地观察到了乙酰胆碱受体依赖性肌肉收缩受损，并且如先前所示，血清中抗乙酰胆碱受体抗体水平需要约50微克/毫升。文中进一步讨论了与每种疾病监测方法相关的优缺点。
