Guder W G, Schmidt U
Hoppe Seylers Z Physiol Chem. 1976 Dec;357(12):1793-800. doi: 10.1515/bchm2.1976.357.2.1793.
Pyruvate kinase and phosphoenolpyruvate carboxykinase activities were determined in microdissected freeze-dried liver cells from the periportal and pericentral area of the liver lobule. Pyruvate kinase activity was measured by a microfluorimetric procedure adapted to 20-200 ng tissue dry weight. In livers from fed rats, its activity was twice as high in the central zone as in the periportal cells; starvation reduced this gradient by decreasing central activities. Phosphoenolpyruvate carboxykinase activity was measured by a microradiochemical technique in 100-300 ng tissue dry weight. In livers from fed rats, this enzyme was nearly 3 times more active in the periportal cells than in the central area. Starvation increased this enzyme in both zones with a more pronounced change in the central cells. The results indicate a heterogeneous distribution of enzymes of carbohydrate metabolism in the liver lobule. Gluconegenesis seems to be localized preferentially in periportal hepatocytes, whereas the glycolytic enzyme was found to be more active in cells surrounding the pericentral liver cells.
在从肝小叶的门周区和中央区显微切割的冻干肝细胞中测定了丙酮酸激酶和磷酸烯醇丙酮酸羧激酶的活性。丙酮酸激酶活性通过适用于20 - 200 ng组织干重的微量荧光测定法进行测量。在喂食大鼠的肝脏中，其活性在中央区是门周细胞中的两倍；饥饿通过降低中央区的活性减小了这种梯度。磷酸烯醇丙酮酸羧激酶活性通过微量放射化学技术在100 - 300 ng组织干重中进行测量。在喂食大鼠的肝脏中，这种酶在门周细胞中的活性比在中央区高近3倍。饥饿使两个区域的这种酶都增加，中央细胞中的变化更明显。结果表明肝小叶中碳水化合物代谢酶存在异质性分布。糖异生似乎优先定位于门周肝细胞中，而糖酵解酶在中央肝细胞周围的细胞中活性更高。
