Castaño J G, Alemany S, Nieto A, Mato J M
J Biol Chem. 1980 Oct 10;255(19):9041-3.
Glucagon produces a time- and dose-dependent activation of phospholipid methyltransferase activity in isolated rat hepatocytes. Half-maximal effect is caused by a dose of glucagon of 1 x 10(-10) M. This activation is due to an increase of the Vmax value of the enzyme, without affecting the Km value for S-adenosylmethionine. Exogenous cyclic AMP added to isolated rat hepatocytes mimics the effect of glucagon, and the activation of phospholipid methyltransferase by a nonsaturating concentration of glucagon is spontaneously reversible within 40 min of incubation.
胰高血糖素在离体大鼠肝细胞中可产生时间和剂量依赖性的磷脂甲基转移酶活性激活作用。1×10⁻¹⁰ M的胰高血糖素剂量可产生半数最大效应。这种激活是由于该酶的Vmax值增加，而不影响S-腺苷甲硫氨酸的Km值。添加到离体大鼠肝细胞中的外源性环磷酸腺苷可模拟胰高血糖素的作用，并且在孵育40分钟内，非饱和浓度的胰高血糖素对磷脂甲基转移酶的激活作用可自发逆转。
