Peng C F, Elders M J, Hughes E R, Hicks D C, Straub K D, Murphy M L
Ann Clin Lab Sci. 1982 Nov-Dec;12(6):484-91.
The injection of cortisol phosphate (0.5 mg per egg) onto the chorioallantoic membrane of embryonic chicks at 12 days incubation depresses the rate of oxygen consumption in heart mitochondria isolated from the chicks 24 or 48 hours after the injection as compared to a saline injected control. The oxygen consumption is depressed using either reduced nicotinamide-adenine dinucleotide (NADH)-linked or flavin adenine dinucleotide (FADH)-linked substrates. The progressive inhibition of oxidation and adenosine triphosphate (ATP) production rate is related to the time after cortisol is injected. The treated mitochondria appear to function differently when NADH-linked and FADH-linked respiratory substrates are compared. Using NADH-linked substrates (site 1), adenosine diphosphate (ADP) was phosphorylated by mitochondria, even though the rate of phosphorylation was decreased; however, when FADH-linked substrates were used, incomplete phosphorylation was observed. The rate and the extent of calcium accumulation by embryonic chick heart mitochondria were also depressed by cortisol. These data suggest a defect in phosphorylation at site 2 following cortisol treatment but not at the site 1 linked energy transducing step. Whether these impairments of mitochondrial function result from catabolic turnover of the mitochondrial membrane components, excessive calcium accumulation by the mitochondria, or from the digestion of mitochondrial constituents, has not been delineated.
在孵化12天时，向鸡胚的绒毛尿囊膜注射磷酸皮质醇（每枚鸡蛋0.5毫克），与注射生理盐水的对照组相比，在注射后24或48小时分离得到的鸡胚心脏线粒体中，氧气消耗速率降低。无论是使用还原型烟酰胺腺嘌呤二核苷酸（NADH）连接的底物还是黄素腺嘌呤二核苷酸（FADH）连接的底物，氧气消耗均降低。氧化和三磷酸腺苷（ATP）产生速率的进行性抑制与注射皮质醇后的时间有关。当比较NADH连接和FADH连接的呼吸底物时，经处理的线粒体似乎功能不同。使用NADH连接的底物（位点1）时，线粒体可使二磷酸腺苷（ADP）磷酸化，尽管磷酸化速率降低；然而，当使用FADH连接的底物时，观察到磷酸化不完全。鸡胚心脏线粒体对钙的积累速率和程度也受到皮质醇的抑制。这些数据表明，皮质醇处理后位点2的磷酸化存在缺陷，但位点1的能量转换步骤没有缺陷。线粒体功能的这些损害是由于线粒体膜成分的分解代谢周转、线粒体过度积累钙，还是由于线粒体成分的消化，目前尚未明确。
