Kraft Norbert O, Inoue Natsuhiko, Mizuno Koh, Ohshima Hiroshi, Murai Tadashi, Sekiguchi Chiharu
Human Factor Research and Technology Division, NASA-Ames Research Center, Moffett Field, CA 94035-1000, USA.
Aviat Space Environ Med. 2002 Nov;73(11):1089-93.
Previous isolation studies have shown increased 24-h urine volumes and body weight gains in subjects. This project examined those and other physiological variables in relationship to sleep motor activity, subjective sleep quality, mood, and complaints during confinement.
Six male and two female subjects lived for 7 d in the National Space Development Agency of Japan's isolation chamber, which simulates the interior of the Japanese Experiment Module. Each 24-h period included 6 h of sleep, 3 meals, and 20 min of exercise. Each morning, subjects completed Sleep Sensation and Complaint Index questionnaires. Catecholamine and creatinine excretion, urine volume, and body weight were measured on the 2 d before and 2 d after confinement, and sleep motor activity was measured during confinement.
Confinement produced no significant change in body weight, urine volume, or questionnaire results. In contrast, epinephrine, norepinephrine, and sleep motor activity exhibited significant differences during confinement (p < 0.05). Higher nocturnal norepinephrine excretion correlated with higher sleep motor activity.
The 24-h epinephrine values were slightly higher than normal throughout the experiment, but lower than for subjects working under time-stress. High sympathetic activity (as indicated by norepinephrine) may have interfered with sleep.
先前的隔离研究表明，受试者的24小时尿量增加且体重上升。本项目研究了这些以及其他生理变量与睡眠运动活动、主观睡眠质量、情绪和禁闭期间不适症状之间的关系。
6名男性和2名女性受试者在日本宇宙开发事业团的隔离舱中生活7天，该隔离舱模拟了日本实验舱的内部环境。每个24小时周期包括6小时睡眠、3餐和20分钟锻炼。每天早晨，受试者完成睡眠感觉和不适症状指数问卷。在禁闭前2天和禁闭后2天测量儿茶酚胺和肌酐排泄量、尿量和体重，并在禁闭期间测量睡眠运动活动。
禁闭期间体重、尿量或问卷结果无显著变化。相比之下，肾上腺素、去甲肾上腺素和睡眠运动活动在禁闭期间表现出显著差异（p<0.05）。夜间去甲肾上腺素排泄量较高与睡眠运动活动较高相关。
在整个实验过程中，24小时肾上腺素值略高于正常水平，但低于在时间压力下工作的受试者。高交感神经活动（以去甲肾上腺素表示）可能干扰了睡眠。
