Wang Jong-Shyan, Li Yu-San, Chen Jin-Chung, Chen Yu-Wen
Graduate Institute of Rehabilitation Science, Center for Gerontological Research, Chang Gung University, Taoyuan, Taiwan.
Arterioscler Thromb Vasc Biol. 2005 Feb;25(2):454-60. doi: 10.1161/01.ATV.0000151987.04607.24. Epub 2004 Nov 29.
Alternating shear stress, which resembles the flow condition in stenotic arteries, induces platelet aggregation. This study investigated how exercise training and deconditioning influence alternating shear-induced platelet aggregation (ASIPA) and clarify the mechanisms underlying ASIPA.
Thirty healthy male sedentary subjects were randomly divided into control and trained groups. The trained men were trained on a bicycle ergometer at approximately 60% of maximal oxygen consumption for 30 minutes per day, 5 days per week for 8 weeks, and then were deconditioned for 8 weeks. The experimental results indicate the following: (1) short-term strenuous exercise increases the extent of ASIPA and is accompanied by increased the von Willebrand factor (vWF) binding and P-selectin expression on platelets in both the control and trained groups, whereas the enhancement of platelet function decreases after exercise training in trained subjects; (2) at rest and immediately after exercise, ASIPA and the vWF binding and P-selectin expression on platelets are reduced by training, but remain unchanged in the control group; and (3) deconditioning reverses the effects of training on resting and postexercise state.
Exercise training suppresses the extent of ASIPA, probably by reducing vWF binding to platelets and P-selectin expression on platelets. However, deconditioning reverses the training effects. This investigation shows that exercise training decreases resting and severe exercise-promoted platelet aggregation induced by alternating shear stress (ASIPA); moreover, this effect is accompanied by reduced the von Willebrand factor binding and P-selectin expression on platelets. However, the effects of training on ASIPA are reversed to the pretraining state after deconditioning.
交替剪切应力类似于狭窄动脉中的血流状况，可诱导血小板聚集。本研究调查了运动训练和去适应如何影响交替剪切诱导的血小板聚集（ASIPA），并阐明ASIPA的潜在机制。
30名健康男性久坐受试者被随机分为对照组和训练组。训练组男性在自行车测力计上以约最大耗氧量的60%进行训练，每天30分钟，每周5天，持续8周，然后进行8周的去适应训练。实验结果表明：（1）短期剧烈运动增加了ASIPA的程度，且对照组和训练组血小板上血管性血友病因子（vWF）结合和P-选择素表达均增加，而训练后训练组受试者血小板功能增强程度降低；（2）休息时和运动后即刻，训练可降低ASIPA以及血小板上的vWF结合和P-选择素表达，但对照组无变化；（3）去适应逆转了训练对休息和运动后状态的影响。
运动训练可能通过减少vWF与血小板的结合以及血小板上P-选择素的表达来抑制ASIPA的程度。然而，去适应逆转了训练效果。本研究表明，运动训练可降低交替剪切应力诱导的静息和剧烈运动促进的血小板聚集（ASIPA）；此外，这种作用伴随着血小板上vWF结合和P-选择素表达的降低。然而，去适应后训练对ASIPA的影响会恢复到训练前状态。
