Foster D M, Berman M
J Lipid Res. 1981 Mar;22(3):506-13.
A quantitative model describing the kinetics of hydrolysis of rat chylomicron acylglycerols by bovine milk lipoprotein lipase has been developed using data from studies on rat lymph chylomicrons containing doubly labeled acylglycerols. The detailed analysis indicates that, in addition to hydrolysis from tri- to di-, di- to mono-, and monoacylglycerol to glycerol, and apparently direct hydrolysis pathway of tri- to monoacylglycerol is also present. This accounts for the transient accumulation of monoacylglycerol seen in some of the experiments. For most hydrolysis steps, a Michaelis-Menten mechanism adequately describes the rate of hydrolysis as a function of lipoprotein lipase concentration. A higher order, more complex mechanism, however, is necessary for the apparent tri- to monoacylglycerol hydrolysis pathway. A mathematical function that describes the way free fatty acid released can control the rates of hydrolysis, and how the presence of the binding sites for free fatty acid on albumin in the incubation medium can modulate this, in included. The model simultaneously satisfies the kinetics of hydrolysis for tri-, di-, and monoacylglycerol together with the kinetics of the glycerol and fatty acid moieties for a wide range of albumin and lipoprotein lipase concentrations.
利用对含有双标记酰基甘油的大鼠淋巴乳糜微粒的研究数据，建立了一个定量模型，用于描述牛乳脂蛋白脂肪酶对大鼠乳糜微粒酰基甘油的水解动力学。详细分析表明，除了从三酰基甘油水解为二酰基甘油、二酰基甘油水解为单酰基甘油以及单酰基甘油水解为甘油外，还存在从三酰基甘油直接水解为单酰基甘油的途径。这解释了在一些实验中观察到的单酰基甘油的短暂积累现象。对于大多数水解步骤，米氏（Michaelis-Menten）机制足以描述水解速率与脂蛋白脂肪酶浓度的函数关系。然而，对于明显的从三酰基甘油到单酰基甘油的水解途径，需要一个更高级、更复杂的机制。该模型还包含一个数学函数，用于描述释放的游离脂肪酸控制水解速率的方式，以及孵育介质中白蛋白上游离脂肪酸结合位点的存在如何调节这种控制。该模型同时满足了在广泛的白蛋白和脂蛋白脂肪酶浓度范围内，三酰基甘油、二酰基甘油和单酰基甘油的水解动力学以及甘油和脂肪酸部分的动力学。
