Asson-Batres M A, Stock M K, Hare J F, Metcalfe J
Heart Research Laboratory, Oregon Health Sciences University, Portland 97201.
Respir Physiol. 1989 Jul;77(1):101-9. doi: 10.1016/0034-5687(89)90033-9.
Heart ventricles from chick embryos incubated in 60% O2 (hyperoxia) on the 16th through the 18th days of incubation were 21% heavier than those from control embryos maintained in 21% O2 (normoxia). Heart ventricles from embyros incubated in 15% O2 (hypoxia) were 8% lighter than controls. Changes in ventricular weight were accompanied by proportional changes in protein content (21% more in hyperoxic ventricles; 8% less in hypoxic ventricles). Ventricular tissue DNA content showed a significant increase in hyperoxia. Tissue protein/DNA ratios were significantly higher in hyperoxia and lower in hypoxia. These data suggest that increased O2 availability led to hypertrophy of chick embryo ventricular cells and an increase in the level of DNA synthesis. Cytochrome oxidase activity per mg DNA was 15-25% higher in hyperoxic ventricles than in hypoxic ventricles. This result is consistent with our previous findings that alterations in O2 availability affect the O2 consumption rate of the chick emryo in ovo, and it provides direct evidence that a phenomenon repeatedly observed in vitro is of importance in vivo. In contrast to the heart, O2 availability did not affect the wet weight, protein or DNA contents, or cytochrome oxidase activity of the chick embryo brain.
在孵化第16天至18天期间于60%氧气（高氧）环境中孵化的鸡胚心室，比在21%氧气（常氧）环境中饲养的对照胚胎的心室重21%。在15%氧气（低氧）环境中孵化的胚胎的心室比对照轻8%。心室重量的变化伴随着蛋白质含量的相应变化（高氧心室中多21%；低氧心室中少8%）。心室组织DNA含量在高氧环境下显著增加。组织蛋白质/DNA比率在高氧环境中显著更高，在低氧环境中更低。这些数据表明，氧气供应增加导致鸡胚心室细胞肥大以及DNA合成水平提高。每毫克DNA的细胞色素氧化酶活性在高氧心室中比在低氧心室中高15% - 25%。这一结果与我们之前的发现一致，即氧气供应的改变会影响鸡胚在蛋内的耗氧率，并且它提供了直接证据，证明在体外反复观察到的一种现象在体内具有重要意义。与心脏不同，氧气供应并未影响鸡胚大脑的湿重、蛋白质或DNA含量，也未影响细胞色素氧化酶活性。
