Summerbell J, Yelland C, Woodhouse K
Department of Medicine (Geriatrics), The University, Newcastle upon Tyne.
Age Ageing. 1990 Mar;19(2):128-30. doi: 10.1093/ageing/19.2.128.
The kinetics of the phase I enzyme aspirin esterase were estimated in plasma from ten young volunteers, seven healthy elderly volunteers, and in ten frail elderly subjects. Maximal reaction velocity at enzyme saturation (vmax) was similar in young and healthy elderly volunteers, but was significantly reduced in the frail elderly. The Michaelis constant (Km) was similar in all three groups. The results suggest that impaired in vitro aspirin metabolism in frail elderly people is due to a reduction in the quantity of enzyme present, rather than a qualitative change in enzyme proteins.
在10名年轻志愿者、7名健康老年志愿者以及10名体弱老年受试者的血浆中对I相酶阿司匹林酯酶的动力学进行了评估。酶饱和时的最大反应速度（vmax）在年轻和健康老年志愿者中相似，但在体弱老年人中显著降低。米氏常数（Km）在所有三组中相似。结果表明，体弱老年人体外阿司匹林代谢受损是由于存在的酶量减少，而非酶蛋白的质量变化。
