Mitsumoto H, Kurahashi K, Jacob J M, McQuarrie I G
Department of Neurology, Cleveland Clinic Foundation, OH 44195.
Muscle Nerve. 1993 May;16(5):542-7. doi: 10.1002/mus.880160517.
To investigate axonal function in a model of early motor neuron disease, we examined fast and slow components of anterograde axonal transport in the less-affected hindlimb motor neurons of wobbler mice. To study the fast component (FC), we injected tritiated amino acids into the lumbar spinal cord and retrieved the sciatic nerve after 2 or 3 h. The transport distance was the extent of the plateau of labeling; regression analysis indicated that FC was 25% slower in wobbler mice than in unaffected littermates (P < 0.01). To study slow component (SC), [35S]methionine was injected. Transport distances were to the peaks of labeling for structural proteins after 2 or 3 weeks. Rates for each subcomponent (SCa and SCb) were unaffected by wobbler disease. Because the rate of retrograde FC is also unaffected (Mitsumoto et al., Muscle & Nerve 13:121-126, 1990), we conclude that wobbler disease specifically retards anterograde FC in less-affected hindlimb motor neurons, whereas all components of axonal transport are retarded in forelimb motor neurons.
为了在早期运动神经元疾病模型中研究轴突功能，我们检测了摇摆小鼠中受影响较小的后肢运动神经元顺行轴突运输的快速和慢速成分。为了研究快速成分（FC），我们将氚标记的氨基酸注入腰脊髓，并在2或3小时后取出坐骨神经。运输距离为标记平台的范围；回归分析表明，摇摆小鼠的FC比未受影响的同窝小鼠慢25%（P < 0.01）。为了研究慢速成分（SC），注射了[35S]甲硫氨酸。运输距离为2或3周后结构蛋白标记的峰值。每个子成分（SCa和SCb）的速率不受摇摆病的影响。由于逆行FC的速率也不受影响（Mitsumoto等人，《肌肉与神经》13:121 - 126，1990），我们得出结论，摇摆病特异性地减缓了受影响较小的后肢运动神经元中的顺行FC，而轴突运输的所有成分在前肢运动神经元中均减缓。
