Febbraio Mark A, Ott Peter, Nielsen Henning Bay, Steensberg Adam, Keller Charlotte, Krustrup Peter, Secher Niels H, Pedersen Bente Klarlund
Copenhagen Muscle Research Centre, University of Copenhagen, Denmark.
J Physiol. 2002 Nov 1;544(3):957-62. doi: 10.1113/jphysiol.2002.025148.
Physical exercise results in the appearance of heat shock protein (HSP) 72 in the circulation that precedes any increase in gene or protein expression in contracting skeletal muscle. In rodents, exercise increases liver HSP72 expression and the hepatosplanchnic viscera are known to release many acute phase proteins. In the present study, we tested the hypothesis that the splanchnic tissue beds release HSP72 during exercise. Seven male subjects performed 120 min of semi-recumbent cycling at 62 +/- 2 % of maximal oxygen uptake. Blood samples were obtained simultaneously from a brachial artery, a femoral vein and the hepatic vein prior to and at 30, 60 and 120 min of exercise. Leg blood flow (LBF) was measured by thermodilution in the femoral vein, and hepatosplanchnic blood flow (HBL) was measured using indocyanine green dye. Net leg and net hepatosplanchnic HSP72 balance were calculated as the product of LBF and femoral venous-arterial HSP72 difference and the product of HBF and hepatic venous-arterial HSP72 difference, respectively. Arterial plasma HSP72 was only detected in one subject at rest but progressively appeared in the arterial samples throughout exercise such that at 120 min it was detected in all subjects (0.88 +/- 0.35 pg l(-1); P < 0.05 compared with rest). The contracting muscle did not, however, contribute to this increase since there was no difference in the femoral venous-arterial HSP72 concentration at any time. Rather, the increase in arterial HSP72 was accounted for, at least in part, by release from the hepatosplanchnic viscera with values increasing (P < 0.05) from undetectable levels at rest to 5.2 +/- 0.2 pg min(-1) after 120 min. These data demonstrate that the splanchnic tissues release HSP72 during exercise and this release is responsible, in part, for the elevated systemic concentration of this protein during exercise.
体育锻炼会使循环系统中出现热休克蛋白（HSP）72，这发生在收缩骨骼肌中基因或蛋白质表达增加之前。在啮齿动物中，运动可增加肝脏HSP72的表达，并且已知肝内脏会释放许多急性期蛋白。在本研究中，我们检验了这样一个假设，即内脏组织床在运动过程中会释放HSP72。七名男性受试者以最大摄氧量的62±2%进行了120分钟的半卧位骑行。在运动前以及运动30、60和120分钟时，同时从肱动脉、股静脉和肝静脉采集血样。通过热稀释法测量股静脉中的腿部血流量（LBF），并使用吲哚菁绿染料测量肝内脏血流量（HBL）。净腿部和净肝内脏HSP72平衡分别计算为LBF与股静脉 - 动脉HSP72差值的乘积以及HBF与肝静脉 - 动脉HSP72差值的乘积。仅在一名受试者休息时检测到动脉血浆HSP72，但在整个运动过程中动脉样本中逐渐出现，以至于在120分钟时所有受试者均检测到（0.88±0.35 pg l(-1)；与休息时相比，P < 0.05）。然而，收缩的肌肉对这种增加没有贡献，因为在任何时候股静脉 - 动脉HSP72浓度均无差异。相反，动脉HSP72的增加至少部分是由于肝内脏的释放，其值从休息时的不可检测水平增加到120分钟后的5.2±0.2 pg min(-1)（P < 0.05）。这些数据表明，内脏组织在运动过程中释放HSP72，并且这种释放部分导致了运动期间该蛋白全身浓度的升高。
