Martin B, Harris A, Hammel T, Malinovsky V
Medical Sciences Program, Indiana University School of Medicine, Bloomington, USA.
Invest Ophthalmol Vis Sci. 1999 Apr;40(5):1011-5.
Although acute dynamic exercise reduces intraocular pressure (IOP), the factors that provoke this response remain ill-defined. To determine whether changes in colloid osmotic pressure (COP) cause the IOP changes during exercise, standardized exercise was performed after dehydration and hydration with isosmotic fluid.
Progressive cycle ergometer exercise to volitional exhaustion was performed after 4 hours' dehydration, and after hydration with 946 ml isosmotic liquid (345 mOsM). In each experiment, venous blood taken before and immediately after exercise was analyzed for hematocrit, plasma protein concentration, total plasma osmolality, and plasma COP.
Exercise in both experiments significantly reduced IOP and elevated COP (each P < 0.01). Dehydration, compared with hydration, also significantly reduced IOP and elevated COP, when measured before and after exercise (P < 0.05). The correlation of mean IOP with mean COP, over the entire range created by varying exercise and hydration statuses, was statistically significant (r = -0.99; P < 0.001). In contrast, other indexes of hydration status, including hematocrit, total plasma osmolality, and plasma protein concentration, failed to change as IOP changed and failed to correlate with IOP, on either a group or individual basis, in conditions of varying levels of exercise and hydration.
Acute dynamic exercise and isosmotic fluid ingestion each seem to change IOP through changes in COP.
尽管急性动态运动可降低眼压（IOP），但引发这种反应的因素仍不明确。为了确定胶体渗透压（COP）的变化是否会导致运动期间眼压的变化，在脱水和用等渗液补液后进行了标准化运动。
在4小时脱水后以及用946毫升等渗液（345毫渗量/千克）补液后，进行递增式自行车测力计运动直至自愿疲劳。在每个实验中，分析运动前和运动后立即采集的静脉血的血细胞比容、血浆蛋白浓度、总血浆渗透压和血浆COP。
两个实验中的运动均显著降低了眼压并升高了COP（各P<0.01）。与补液相比，脱水在运动前后测量时也显著降低了眼压并升高了COP（P<0.05）。在由不同运动和补液状态所形成的整个范围内，平均眼压与平均COP的相关性具有统计学意义（r=-0.99；P<0.001）。相比之下，在不同运动和补液水平的条件下，包括血细胞比容、总血浆渗透压和血浆蛋白浓度在内的其他补液状态指标并未随眼压变化而改变，且在组内或个体水平上均与眼压无相关性。
急性动态运动和摄入等渗液似乎均通过COP的变化来改变眼压。
