Cummiskey J M, Simon L M, Theodore J, Ryan U S, Robin E D
Exp Lung Res. 1981 Aug;2(3):155-63. doi: 10.3109/01902148109052311.
Endothelial cells function under conditions of different oxygen availability under physiologic conditions and a variety of pathologic states. We determined the effect of normal and low O2 tensions on three key bioenergetic enzymes [pyruvate kinase (ATP:pyruvate phosphotransferase, EC 2.7.1.40), phosphofructokinase (ATP:D-fructose-6-phosphate 1-phosphotransferase, EC 27.1.11) and cytochrome aa3] in culture-maintained endothelial cells derived from calf pulmonary artery and aorta. Endothelial cells derived from pulmonary artery and aorta demonstrate similar bioenergetic enzyme activities when exposed to the same PO2 in vitro. Endothelial cells exposed to hypoxia in vitro for 48-96 hr show significantly increase activities of 2 key glycolytic enzymes: pyruvate kinase, and phosphofructokinase. Freshly isolated intimal strips from calf pulmonary artery (normal PO2 = 40 torr) show significantly greater activities of PyKi than aortic intimal strips (normal PO2 = 90 torr), suggesting that a similar pattern occurs in vivo. The data suggest that both cell types have a common bioenergetic pattern which is genetically determined and that this pattern is modified by regulatory mechanisms geared to ambient O2 tension. As endothelial cells of both types are not uncommonly exposed to hypoxic conditions, these regulatory mechanisms may play an important role in maintaining vascular integrity.
在生理条件和多种病理状态下，内皮细胞在不同氧供应条件下发挥功能。我们测定了正常和低氧张力对源自小牛肺动脉和主动脉的培养内皮细胞中三种关键生物能量酶[丙酮酸激酶（ATP：丙酮酸磷酸转移酶，EC 2.7.1.40）、磷酸果糖激酶（ATP：D-果糖-6-磷酸1-磷酸转移酶，EC 27.1.11）和细胞色素aa3]的影响。当在体外暴露于相同的氧分压时，源自肺动脉和主动脉的内皮细胞表现出相似的生物能量酶活性。体外暴露于低氧48 - 96小时的内皮细胞显示两种关键糖酵解酶的活性显著增加：丙酮酸激酶和磷酸果糖激酶。从小牛肺动脉新鲜分离的内膜条（正常氧分压 = 40托）显示丙酮酸激酶的活性明显高于主动脉内膜条（正常氧分压 = 90托），这表明在体内也会出现类似的模式。数据表明，这两种细胞类型具有共同的由基因决定的生物能量模式，并且这种模式会被针对环境氧张力的调节机制所改变。由于这两种类型的内皮细胞经常会暴露于低氧条件下，这些调节机制可能在维持血管完整性方面发挥重要作用。
