Anastasia J V, McCarl R L
J Cell Biol. 1973 Apr;57(1):109-16. doi: 10.1083/jcb.57.1.109.
This paper reports the determination of the ability of rat heart cells in culture to release [(14)C]palmitate from its triglyceride and to oxidize this fatty acid and free [(14)C]palmitate to (14)CO(2) when the cells are actively beating and when they stop beating after aging in culture. In addition, the levels of glucose, glycogen, and ATP were determined to relate the concentration of these metabolites with beating and with cessation of beating. When young rat heart cells in culture are actively beating, they oxidize free fatty acids at a rate parallel with cellular ATP production. Both fatty acid oxidation and ATP production remain constant while the cells continue to beat. Furthermore, glucose is removed from the growth medium by the cells and stored as glycogen. When cultured cells stop beating, a decrease is seen in their ability to oxidize free fatty acids and to release them from their corresponding triglycerides. Concomitant with decreased fatty acid oxidation is a decrease in cellular levels of ATP until beating ceases. Midway between initiation of cultures and cessation of beating the cells begin to mobilize the stored glycogen. When the growth medium is supplemented with cortisol acetate and given to cultures which have ceased to beat, reinitiation of beating occurs. Furthermore, all decreases previously observed in ATP levels, fatty acid oxidation, and esterase activity are restored.
本文报道了在培养的大鼠心脏细胞中，当细胞处于活跃搏动状态以及在培养中老化后停止搏动时，测定其从甘油三酯中释放[¹⁴C]棕榈酸以及将该脂肪酸和游离[¹⁴C]棕榈酸氧化为¹⁴CO₂的能力。此外，还测定了葡萄糖、糖原和ATP的水平，以关联这些代谢物的浓度与搏动及搏动停止的关系。当培养的幼龄大鼠心脏细胞处于活跃搏动状态时，它们以与细胞ATP产生平行的速率氧化游离脂肪酸。在细胞继续搏动期间，脂肪酸氧化和ATP产生均保持恒定。此外，细胞从生长培养基中摄取葡萄糖并储存为糖原。当培养的细胞停止搏动时，其氧化游离脂肪酸并将它们从相应甘油三酯中释放出来的能力会下降。伴随着脂肪酸氧化减少的是细胞内ATP水平下降，直至搏动停止。在培养开始至搏动停止的中途，细胞开始动用储存的糖原。当向已停止搏动的培养物中添加醋酸皮质醇时，搏动会重新开始。此外，先前观察到的ATP水平、脂肪酸氧化和酯酶活性的所有下降均得以恢复。
