Ishihara A, Ohira Y, Roy R R, Nagaoka S, Sekiguchi C, Hinds W E, Edgerton V R
Laboratory of Neurochemistry, Faculty of Integrated Human Studies, Kyoto University, Japan.
Acta Anat (Basel). 1996;157(4):303-8. doi: 10.1159/000147892.
Succinate dehydrogenase (SDH) activities and soma cross-sectional areas (CSA) of neurons in the dorsolateral region of the ventral horn at the L5 segmental level of the spinal cord in the rat were determined after 14 days of spaceflight and after 9 days of recovery on earth. The results were compared to those in age-matched ground-based control rats. Spinal cords were quick-frozen, and the SDH activity and CSA of a sample of neurons with a visible nucleus were determined using a digitizer and a computer-assisted image analysis system. An inverse relationship between CSA and SDH activity of neurons was observed in all groups of rats. No change in mean CSA or mean SDH activity or in the size distribution of neurons was observed following spaceflight or recovery. However, there was a selective decrease in the SDH activity of neurons with soma CSA between 500 and 800 microns2 in the flight rats, and this effect persisted for at least 9 days following return to 1 g. It remains to be determined whether the selected population of motoneurons or the specific motor pools affected by spaceflight may be restricted to specific muscles.
在大鼠脊髓L5节段水平的腹角背外侧区域，测定了太空飞行14天后及返回地球恢复9天后神经元的琥珀酸脱氢酶（SDH）活性和胞体横截面积（CSA）。将结果与年龄匹配的地面对照大鼠进行比较。脊髓快速冷冻，使用数字化仪和计算机辅助图像分析系统测定有可见细胞核的神经元样本的SDH活性和CSA。在所有大鼠组中均观察到神经元的CSA与SDH活性呈负相关。太空飞行或恢复后，未观察到平均CSA、平均SDH活性或神经元大小分布的变化。然而，飞行大鼠中胞体CSA在500至800平方微米之间的神经元的SDH活性有选择性降低，并且这种效应在返回1g环境后至少持续9天。受太空飞行影响的选定运动神经元群体或特定运动池是否仅限于特定肌肉仍有待确定。
