Schmidt A, Maier C, Schaller G, Nowotny P, Bayerle-Eder M, Buranyi B, Luger A, Wolzt M
Department of Medicine III, University of Vienna, and Ludwig Boltzmann Institute for Experimental Endocrinology, Vienna.
Horm Metab Res. 2004 Mar;36(3):174-7. doi: 10.1055/s-2004-814342.
Exercise is a potent, dose-dependent stimulus of growth hormone (GH) secretion. The hypothalamic peptides, GH-releasing hormone (GHRH) and somatostatin are regarded as major regulators of this stimulation. The role of the stomach-derived peptide ghrelin, which has been shown to exert strong GH releasing effects, has not been fully characterized yet. We therefore studied GH and ghrelin plasma concentrations in response to graded levels of exercise in eight healthy young volunteers. After determination of their individual maximal exercise capacity, all individuals underwent a treadmill exercise at 50 %, 70 %, and 90 % of maximum oxygen consumption (VO (2)max) on different days. Maximal GH response to exercise was observed after 40 minutes at 50 % VO (2)max and after 20 minutes at 70 and 90 % VO (2max). GH serum concentrations increased significantly at all three exercise intensities (GH peak concentrations were 5.8 +/- 2.3 ng/ml, 12.0 +/- 3.2 ng/ml, and 9.8 +/- 4.7 ng/ml, respectively). In contrast, ghrelin plasma concentrations remained unchanged at all three workloads. Assuming that the sensitivity of the GH neuroendocrine/metabolic regulation of GH is unaltered, ghrelin does not participate in the regulation of the GH response to exercise in healthy males.
运动是生长激素（GH）分泌的一种强效、剂量依赖性刺激因素。下丘脑肽类，即生长激素释放激素（GHRH）和生长抑素，被视为这种刺激的主要调节因子。胃源性肽ghrelin已被证明具有强大的生长激素释放作用，但其作用尚未完全明确。因此，我们研究了8名健康年轻志愿者在不同强度运动下的GH和ghrelin血浆浓度。在测定他们各自的最大运动能力后，所有个体在不同日期分别以最大耗氧量（VO₂max）的50%、70%和90%进行跑步机运动。在50%VO₂max运动40分钟后以及70%和90%VO₂max运动20分钟后观察到运动对GH的最大反应。在所有三种运动强度下，GH血清浓度均显著升高（GH峰值浓度分别为5.8±2.3 ng/ml、12.0±3.2 ng/ml和9.8±4.7 ng/ml）。相比之下，在所有三种运动负荷下，ghrelin血浆浓度均保持不变。假设GH神经内分泌/代谢调节对GH的敏感性未改变，ghrelin不参与健康男性运动时GH反应的调节。
