Watkins A M, Cheek D J, Harvey A E, Blair K E, Mitchell J B
Department of Kinesiology, TCU, Fort Worth, TX 76129, USA.
Int J Sports Med. 2008 Apr;29(4):269-76. doi: 10.1055/s-2007-965331. Epub 2007 Sep 18.
The purpose of this research was to determine the effect of a 7-day heat acclimation protocol on HSP-72 expression in human skeletal muscle, and to examine the relationships between molecular and physiological markers of heat acclimation. Ten recreationally active male subjects (age = 23.3 +/- 2.81 yrs, VO(2peak) = 3.85 +/- 0.11 L . min (-1)) completed a 7-day heat acclimation protocol consisting of cycling at 75 % of VO(2peak) in a hot environment (39.5 degrees C, 27 % RH). Muscle biopsies were obtained on days 1 (HTT1) and 7 (HTT2) prior to, 6 h post, and 24 h postexercise to measure HSP-72 protein via SDS-PAGE and silver staining. Core rectal temperatures (T(C)), intramuscular temperatures (T(IM)), skin temperatures (T(SK)), heart rate (HR), oxygen uptake (VO(2)), sweat rate (SR), and plasma cortisol were measured. TC, HR, and plasma cortisol were significantly lower in HTT2 than HTT1 (p < or = 0.05). No significant differences were seen for VO(2), TIM, TSK, or SR when comparing HTT2 with HTT1 (p < or = 0.05). No significant time or day x time interactions were detected for HSP-72 expression (24.48 +/- 2.55 vs. 25.04 +/- 1.43 ng/microg protein for HTT1 and HTT2, respectively, p < or = 0.05). Evidence of heat acclimation was seen at the physiological level; however, no evidence of enhanced thermotolerance at the cellular level was indicated by HSP-72 expression.
本研究的目的是确定为期7天的热适应方案对人体骨骼肌中热休克蛋白72（HSP - 72）表达的影响，并研究热适应的分子和生理标志物之间的关系。十名有运动习惯的男性受试者（年龄 = 23.3 ± 2.81岁，最大摄氧量（VO₂peak） = 3.85 ± 0.11 L·min⁻¹）完成了一项为期7天的热适应方案，该方案包括在炎热环境（39.5℃，相对湿度27%）中以最大摄氧量的75%进行骑行。在第1天（HTT1）和第7天（HTT2）运动前、运动后6小时和运动后24小时采集肌肉活检样本，通过十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳（SDS - PAGE）和银染法测量HSP - 72蛋白。测量了直肠核心温度（T(C)）、肌肉温度（T(IM)）、皮肤温度（T(SK)）、心率（HR）、摄氧量（VO₂）、出汗率（SR）和血浆皮质醇。与HTT1相比，HTT2中的直肠核心温度、心率和血浆皮质醇显著降低（p≤0.05）。比较HTT2和HTT1时，摄氧量、肌肉温度、皮肤温度或出汗率未见显著差异（p≤0.05）。未检测到HSP - 72表达的显著时间或日×时间交互作用（HTT1和HTT2的HSP - 72表达分别为24.48 ± 2.55 ng/μg蛋白和25.
