Ishihara Akihiko, Kawano Fuminori, Ishioka Noriaki, Oishi Hirotaka, Higashibata Akira, Shimazu Toru, Ohira Yoshinobu
Laboratory of Neurochemistry, Graduate School of Human and Environmental Studies, Kyoto University, 606-8501, Japan.
Int J Dev Neurosci. 2003 Dec;21(8):461-9. doi: 10.1016/j.ijdevneu.2003.08.003.
Cell body sizes and oxidative enzyme (succinate dehydrogenase) activities of spinal motoneurons innervating the soleus muscle were determined in rats ranging in postnatal age from 3 to 13 weeks. The soleus motoneurons were labeled by a retrograde neuronal tracer, nuclear yellow. The mean cell body sizes of motoneurons increased from 3 to 7 weeks of age, while the mean succinate dehydrogenase activities of motoneurons decreased from 3 to 7 weeks of age. There were no changes in mean cell body size or mean succinate dehydrogenase activity of motoneurons from 7 to 13 weeks of age. An inverse relationship between cell body size and succinate dehydrogenase activity of motoneurons was observed, irrespective of age. These results indicate that motoneurons innervating the rat soleus muscle show the adult pattern of cell body size and succinate dehydrogenase activity at an earlier stage of postnatal growth, 7 weeks of age.
在出生后3至13周的大鼠中，测定了支配比目鱼肌的脊髓运动神经元的细胞体大小和氧化酶（琥珀酸脱氢酶）活性。通过逆行神经元示踪剂核黄对支配比目鱼肌的运动神经元进行标记。运动神经元的平均细胞体大小在3至7周龄时增加，而运动神经元的平均琥珀酸脱氢酶活性在3至7周龄时降低。在7至13周龄时，运动神经元的平均细胞体大小或平均琥珀酸脱氢酶活性没有变化。无论年龄如何，均观察到运动神经元的细胞体大小与琥珀酸脱氢酶活性之间呈负相关。这些结果表明，支配大鼠比目鱼肌的运动神经元在出生后生长的早期阶段（7周龄）就呈现出成年期的细胞体大小和琥珀酸脱氢酶活性模式。
