Amino acid loss during volume regulatory decrease in cultured chick heart cells.
Amino acid loss during volume regulatory decrease in cultured chick heart cells.
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培养的鸡心细胞体积调节减少期间的氨基酸损失。
DOI：
10.1152/ajpcell.1993.264.1.c136
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Lieberman,M
中科院分区：
文献类型：
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作者：
Rasmusson,RL;Davis,DG;Lieberman,M
使用光学、生化和核磁共振方法研究了经低体量处理的培养鸡心细胞制剂的体积调节机制。这种方法提供了时间依赖性反应的分辨率，这些反应通常可能被完整心肌制剂的复杂形态所掩盖。在低渗溶液中，细胞在 3 分钟内膨胀至峰值体积，并缓慢调节至原始体积（调节体积减少，RVD）。低渗处理后细胞返回等渗溶液后，细胞收缩至稳态体积，该体积大大小于对照溶液中的初始体积。在无 Cl(-) 的条件下，低渗肿胀也可能引起剧烈的 RVD。通过原子吸收光谱测量无机阳离子损失，通过 1H 核磁共振和高压液相色谱技术测量有机溶质损失表明，暴露于低体溶液后观察到的 RVD 部分是由牛磺酸、谷氨酸、天冬氨酸和甘氨酸的大量损失以及无机离子 (Na+、K+) 的损失介导的。氨基酸的低渗激活转运也与谷氨酸和天冬氨酸的产生有关。氨基酸的体积调节释放和产生对心肌细胞的代谢和功能完整性具有重要影响。
Mechanisms of volume regulation in hyposomotically treated cultured chick heart cell preparations were studied using optical, biochemical, and nuclear magnetic resonance methods. This approach afforded the resolution of time-dependent responses that might ordinarily be obscured by the complex morphology of intact cardiac muscle preparations. In hyposmotic solutions, cells swelled to a peak volume within 3 min and slowly regulated toward original volume (regulatory volume decrease, RVD). Upon return of the cells to isosmotic solution following hyposmotic treatment, the cells shrank to a steady-state volume that was substantially less than the initial volume in control solution. A vigorous RVD could also be elicited by hyposmotic swelling under Cl(-)-free conditions. Measurement of both inorganic cation loss via atomic absorption spectroscopy and organic solute loss via 1H-nuclear magnetic resonance and high-pressure liquid chromatographic techniques revealed that the RVD observed following exposure to hyposomotic solutions was mediated in part by a substantial loss of taurine, glutamate, aspartate, and glycine as well as loss of inorganic ions (Na+,K+). The hyposmotically activated transport of amino acids was also associated with the production of glutamate and aspartate. The volume regulatory release and production of amino acids have significant implications for the metabolic and functional integrity of cardiac cells.