Okajima Y, Maloney F P
John L McClellan Memorial Veterans Administration Hospital, Little Rock, Arkansas.
Am J Phys Med Rehabil. 1989 Apr;68(2):66-9. doi: 10.1097/00002060-198904000-00004.
Exercised rats have larger myelinated nerve fibers than sedentary rats and exercised rats with acrylamide neuropathy have smaller fibers than acrylamide-treated sedentary rats. These nerve fiber changes were the result of work hypertrophy and overwork atrophy, respectively. This study was designed to reassess morphologic changes in nerves after overwork was induced in rats with acrylamide neuropathy and to test the effects of rest before and after an overwork period in rats with acrylamide neuropathy. The 4-week-old rats divided into four groups of eight rats. Acrylamide was administered to three groups (Groups 2, 3, and 4) to induce subacute paralysis followed by gradual ameriolation. Group 3 was exercised for the first 5 weeks and was rested for the last 5 weeks. Group 4 was exercised for the last 5 weeks. The diameter distribution of myelinated fibers of the tibial and sural nerves was analyzed. The percentage of larger myelinated fibers was decreased in all acrylamide-treated groups. The average values of fiber diameters in Group 4 were significantly smaller than injected sedentary animals (Group 2) or those with rest (Group 3), whereas no significant difference was found between the latter groups. Axonal degeneration of teased fibers was assessed in the tibial and sural nerves. The percentage of axonal degenerated fibers in exercised animals (Group 4) was significantly higher than in the other acrylamide-injected groups (Groups 2 and 3). This study supports the concept that acrylamide neuropathy worsens with moderate intensity of running activities for a prolonged period and that recovery may occur if vigorous exercise is avoided.
运动大鼠比久坐不动的大鼠有更大的有髓神经纤维，而患有丙烯酰胺神经病变的运动大鼠的纤维比经丙烯酰胺处理的久坐不动的大鼠更小。这些神经纤维变化分别是工作性肥大和过度劳累性萎缩的结果。本研究旨在重新评估丙烯酰胺神经病变大鼠过度劳累后神经的形态学变化，并测试丙烯酰胺神经病变大鼠过度劳累前后休息的效果。将4周龄的大鼠分为四组，每组8只。对三组（第2、3和4组）给予丙烯酰胺以诱导亚急性麻痹，随后逐渐改善。第3组在最初5周进行运动，在最后5周休息。第4组在最后5周进行运动。分析胫神经和腓肠神经有髓纤维的直径分布。在所有丙烯酰胺处理组中，较大有髓纤维的百分比均降低。第4组纤维直径的平均值显著小于注射丙烯酰胺的久坐不动动物（第2组）或休息的动物（第3组），而后两组之间未发现显著差异。在胫神经和腓肠神经中评估 teased 纤维的轴突变性。运动动物（第4组）中轴突变性纤维的百分比显著高于其他丙烯酰胺注射组（第2组和第3组）。本研究支持以下观点：丙烯酰胺神经病变会因长时间中等强度的跑步活动而恶化，并且如果避免剧烈运动，可能会出现恢复。
