Effects of graded hypoxia on contraction of cultured chick embryo ventricular cells.
Effects of graded hypoxia on contraction of cultured chick embryo ventricular cells.
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分级缺氧对培养鸡胚心室细胞收缩的影响。
DOI：
10.1152/ajpheart.1980.239.5.h651
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发表时间：
1980
期刊：
影响因子：
--
通讯作者：
Smith,TW
中科院分区：
文献类型：
--
作者：
Barry,WH;Pober,J;Marsh,JD;Frankel,SR;Smith,TW
由于弥散限制估计的不确定性，在完整的心肌组织中，给定的氧张力 (Po2) 下降与收缩功能抑制程度之间的定量关系很难确定。因此，我们研究了缺氧对具有最小系列扩散屏障的系统中收缩性的影响，该系统由从 10 日龄鸡胚心室培养的自发收缩单层内的单细胞组成。当灌注液 Po2 低于 12 mmHg 时，细胞壁运动的幅度和速度会在 3 至 4 分钟内发生可逆性降低，而当 Po2 值低于 4 mmHg 时，最大降低幅度约为对照水平的 30%。复氧后，收缩幅度和速度在不到 15 秒的时间内恢复。用 0.1 mM 碘乙酸抑制糖酵解会导致缺氧期间收缩幅度更显着降低，搏动速率显着减慢。此外，收缩功能受损的临界 Po2 增加至约 16 mmHg。因此，源自无氧糖酵解的高能磷酸盐似乎能够在这些培养的心脏细胞短暂缺氧期间支持降低的收缩性水平。
The quantitative relationship between a given decrease in O2 tension (Po2) and the degree of depression of contractile function is difficult to define in intact myocardial tissues because of uncertainty in estimation of diffusion limitations. We therefore have studied the effects of hypoxia on contractility in a system with minimal series diffusion barriers, consisting of single cells within spontaneously contracting monolayers cultured from 10-day-old chick embryo ventricles. Reversible decreases in amplitude and velocity of cell wall motion occurred over a 3- to 4-min period when perfusate Po2 was less than 12 mmHg, and a maximum depression to about 30% of control levels occurred at Po2 values less than 4 mmHg. On reoxygenation, recovery of amplitude and velocity of contraction occurred in less than 15 s. Inhibition of glycolysis with 0.1 mM iodoacetate resulted in a more marked decrease in contraction amplitude and a significant slowing of beating rate during hypoxia. In addition, the critical Po2 at which contractile function became impaired was increased to about 16 mmHg. Thus, high-energy phosphates derived from anaerobic glycolysis appear to be able to support a reduced level of contractility during brief periods of hypoxia in these cultured heart cells.