Development of Ion Metabolism in Reaggregated Brain Cell Cultures
Development of Ion Metabolism in Reaggregated Brain Cell Cultures
复制标题
重新聚集的脑细胞培养物中离子代谢的发展
作者：
M. Marks;N. Seeds
摘要：小鼠脑细胞重聚集体已被用于研究钠和钾依赖性哇巴因敏感性腺苷磷酸水解酶（Na+，K +-ATP酶）活性的变化以及发育过程中86 Rb+摄取和排出的变化。这些培养物中的Na+，K+-ATP酶活性有两种哇巴因可降解的成分，在培养的第3天至第17天之间，这两种成分都增加了数倍。然而，这种增加小于发育中的大脑。无论是总或细胞外水或在Na+和K+的平衡水平发生在发展过程中的变化不大。在培养过程中，10分钟孵育测量的86 Rb+摄取仅显示出适度增加，而86 Rb+从预装载有示踪剂的重聚集体中的排出增加了约四倍。出口由K +非依赖性和K+刺激组分组成，K+刺激组分贡献了大部分发育变化。当摄取率进行校正的发展变化的贡献退出，这些利率被发现增加以及。在发育过程中，~（86）Rb ~+摄取与Na ~+，K ~+-ATP酶活性密切相关。酶活性和86 Rb+摄取和排出的发育变化模式表明，虽然离子的稳态水平几乎没有变化，但离子运动速率显著增加。
Abstract: Mouse brain cell reaggregates have been used to study changes in sodium‐ and potassium‐dependent ouabain‐sensitive adenosine phos‐phohydrolase (Na+,K + ‐ATPase) activity and in 86Rb+ uptake and exit during development. Na+, K+‐ATPase activity in these cultures has two ouabain‐inhibitable components, both of which increased severalfold between day 3 and day 17 in culture. This increase, however, was less than that in developing brain. Little change in either total or extracellular water or in the equilibrium levels of Na+ and K+ occurred during development. The uptake of 86Rb+ measured a 10‐min incubation showed only a modest increase during culture, whereas the exit of 86Rb+ from reaggregates preloaded with the tracer increased approximately fourfold. The exit consisted of both K +‐independent and K+ ‐stimulated components and the K+ ‐stimulated fraction contributed most of the developmental change. When uptake rates were corrected for the contribution of the developmental changes in exit, these rates were found to increase as well. The 86Rb+ uptake correlated closely with the activity of the Na+, K+‐ATPase during development. The pattern of developmental changes in enzyme activity and 86Rb+ uptake and exit suggest that, while little change in the steady‐state levels of the ions occurred, the rates of ion movement increase markedly.