Appenzeller O
Department of Neurology, University of New Mexico School of Medicine, Albuquerque 87131.
Funct Neurol. 1987 Oct-Dec;2(4):473-85.
Behavioral, physiologic and exertional fatigue is differently defined, though symptoms are similar. The beneficial effect of amantadine on fatiguability in multiple sclerosis is accompanied by neuropeptide and lactate changes in the circulation. Exercise sometimes overwhelms temperature regulating mechanisms and may be associated with heat stroke. Endogenous opioids are markedly increased in the circulation during heat stroke and the use of specific opioid antagonists therapeutically has been proposed for heat stroke. Sympathetic activity changes in endurance trained subjects and vasoconstrictor responses are markedly attenuated. Similar changes occur in parasympathetic function which can be abnormal in up to 90% of endurance trained subjects. Hormonal secretion during prolonged exertion is altered and the normal signals (inhibiting or activating feedback mechanisms) are different in endurance trained subjects. Altitude, associated with acute mountain sickness, is also accompanied by an increase in cranial bloodflow. Circadian and temporal variation in autonomic function are manifest by changes in mast cell numbers and 5-HT containing nerve fibers in temple skin of patients with cluster headache. The remission rate induced by vagal stimulation in subjects with intractable hiccups is also affected by circadian hormonal or neurogenic influences.
行为性、生理性和运动性疲劳的定义不同，尽管症状相似。金刚烷胺对多发性硬化症疲劳性的有益作用伴随着循环中神经肽和乳酸的变化。运动有时会超出体温调节机制，可能与中暑有关。中暑期间循环中内源性阿片类物质显著增加，有人提议使用特定的阿片类拮抗剂治疗中暑。耐力训练受试者的交感神经活动发生变化，血管收缩反应明显减弱。副交感神经功能也会出现类似变化，在高达90%的耐力训练受试者中可能异常。长时间运动期间激素分泌会发生改变，耐力训练受试者的正常信号（抑制或激活反馈机制）也有所不同。与急性高山病相关的高原环境也伴随着颅血流量增加。丛集性头痛患者颞部皮肤中肥大细胞数量和含5-羟色胺神经纤维的变化体现了自主神经功能的昼夜节律和时间变化。迷走神经刺激对顽固性呃逆患者诱导的缓解率也受昼夜激素或神经源性影响。
