无膜胸腺淋巴细胞核中的钾潴留

Potassium retention in membraneless thymus lymphocyte nuclei.

作者信息

Kellermayer M, Rouse D, Gyorkey F, Hazlewood C F

出版信息

Physiol Chem Phys Med NMR. 1984;16(6):503-11.

Abstract

Nonionic detergents, Triton X-100 and Brij 58, removed lipoid membranes of suspended thymus lymphocytes within 5 minutes. The mobilization and solubilization of cytoplasmic and nuclear proteins occurred much faster (less than 5 minutes) with Triton X-100 treatment than with Brij 58 treatment (less than 10 minutes). In Triton X-100 treated cells the loss of K+ was complete within 5 minutes whereas with Brij 58 treatment the K+ loss was not complete after 10 minutes. Thus, the high concentration of K+ and the low concentration of Na+ in the nuclei can remain near normal for minutes in the absence of membrane structures. If the ions were in free solution within the cells, disruption of membrane integrity should lead to equilibration of the ions with external media within seconds. The decrease of K+ in the Brij 58 treated cells with exposure time was correlated with the solubilization of the proteins. These results support the view that K+ and Na+ are not freely dissolved in the cellular water, but are co-compartmentalized with proteins inside the living cell.

摘要

非离子型去污剂Triton X-100和Brij 58在5分钟内就能去除悬浮胸腺淋巴细胞的类脂膜。与Brij 58处理（不到10分钟）相比，Triton X-100处理使细胞质和核蛋白的动员和溶解发生得更快（不到5分钟）。在经Triton X-100处理的细胞中，K⁺在5分钟内完全流失，而经Brij 58处理的细胞在10分钟后K⁺流失仍未完成。因此，在没有膜结构的情况下，细胞核中高浓度的K⁺和低浓度的Na⁺能在数分钟内保持接近正常水平。如果离子在细胞内处于自由溶液状态，那么膜完整性的破坏应该会导致离子在几秒钟内与外部介质达到平衡。Brij 58处理的细胞中K⁺随暴露时间的减少与蛋白质的溶解相关。这些结果支持了这样一种观点，即K⁺和Na⁺并非自由溶解在细胞水中，而是在活细胞内与蛋白质共同分隔存在。