Opstad P K, Wiik P, Haugen A H, Skrede K K
Norwegian Defence Research Establishment, Division for Environmental Toxicology, Kjeller.
Eur J Appl Physiol Occup Physiol. 1994;69(5):371-5. doi: 10.1007/BF00865397.
The mechanism for adrenergic desensitisation during physical stress was studied by measuring [125I] cyanopindolol ([125I]CYP) binding sites and the adrenaline stimulated cyclic adenosine monophosphate (cAMP) responses in peripheral blood leucocytes from ten male cadets during a 5-day military training course. The cadets had physical activities around the clock corresponding to a daily energy consumption of about 40,000 kJ but with an intake of only 2,000 kJ, and only 1-3 h of sleep in the 5 days. During the course, the maximal cAMP response to adrenaline stimulation was reduced to about 45% in granulocytes and to 52% in mononuclear cells, and the half maximal response was obtained only at 5-10 times higher adrenaline concentrations than in the control experiment. The binding sites for [125I]-CYP in mononuclear cells increased during the course. However, [125I]-CYP measured not only surface receptors but also intracellular receptors and might even have represented other binding sites. In conclusion, this study showed that decreased cAMP response to adrenergic stimulation would seem to be one of the mechanisms behind adrenergic desensitisation during stress.
通过测量10名男性军校学员在为期5天的军事训练课程期间外周血白细胞中[125I]氰吲哚洛尔（[125I]CYP）结合位点以及肾上腺素刺激的环磷酸腺苷（cAMP）反应，研究了身体应激期间肾上腺素能脱敏的机制。学员们全天进行体育活动，每日能量消耗约40000千焦，但摄入量仅为2000千焦，且5天内仅睡眠1 - 3小时。在训练过程中，粒细胞对肾上腺素刺激的最大cAMP反应降至约45%，单核细胞降至52%，且仅在比对照实验高5 - 10倍的肾上腺素浓度下才能获得半数最大反应。单核细胞中[125I]-CYP的结合位点在训练过程中增加。然而，[125I]-CYP不仅测量表面受体，还测量细胞内受体，甚至可能代表其他结合位点。总之，本研究表明，应激期间肾上腺素能脱敏背后的机制之一似乎是对肾上腺素能刺激的cAMP反应降低。
