Donevan R H, Andrew G M
Med Sci Sports Exerc. 1987 Jun;19(3):229-33.
The present study was undertaken to define the response of plasma beta-endorphin immunoreactivity (ir-BE) to exercise of increasing intensity. Nineteen healthy males performed continuous exercise for 32 min on a cycle ergometer, comprised of 8-min bouts at %VO2max approximating 25, 50, and 75% of maximal exercise. Venous blood samples were collected before exercise (T = -20 and 0 min), during exercise (T = 8, 16, 24, and 32 min), and in recovery (T = +15, +30 min). Ir-BE in plasma was measured by radioimmunoassay using Immuno Nuclear assay kits. Plasma ir-BE level (pg X ml-1) was not altered from pre-exercise (18.3 +/- 1.3) after 8 min of exercise at 25 and 50% VO2max intensity; however, ir-BE rose significantly after 8 min of 75% VO2max work intensity (27.1 +/- 2.4) and was further elevated at maximal exercise (74.1 +/- 8.6). Ir-BE level remained elevated 15 min (60.9 +/- 8.1) and 30 min (35.2 +/- 5.2) post-exercise. The response pattern was further characterized by a significant (P less than 0.05) inter-individual variation, both at rest and during exercise; also, regression analysis indicated the ir-Be levels attained at maximal exercise were inversely related to the relative VO2max (ml X kg-1 X min-1) of the subject (predicted ir-BE = 248.2 - 3.39 VO2max; r = -0.397, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
本研究旨在确定血浆β-内啡肽免疫反应性（ir-BE）对强度不断增加的运动的反应。19名健康男性在自行车测力计上进行了32分钟的持续运动，包括在接近最大运动强度25%、50%和75%的最大摄氧量（%VO2max）下各进行8分钟的运动。在运动前（T = -20和0分钟）、运动期间（T = 8、16、24和32分钟）以及恢复期间（T = +15、+30分钟）采集静脉血样。使用免疫核分析试剂盒通过放射免疫分析法测量血浆中的ir-BE。在25%和50%VO2max强度下运动8分钟后，血浆ir-BE水平（pg X ml-1）与运动前（18.3 +/- 1.3）相比没有变化；然而，在75%VO2max工作强度下运动8分钟后，ir-BE显著升高（27.1 +/- 2.4），并在最大运动时进一步升高（74.1 +/- 8.6）。运动后15分钟（60.9 +/- 8.1）和30分钟（35.2 +/- 5.2），ir-BE水平仍保持升高。这种反应模式的进一步特征是在静息和运动期间个体间存在显著（P < 0.05）差异；此外，回归分析表明，最大运动时达到的ir-Be水平与受试者的相对最大摄氧量（ml X kg-1 X min-1）呈负相关（预测ir-BE = 248.2 - 3.39 VO2max；r = -0.397，P < 0.05）。（摘要截短为250字）
