Le Quan Sang K H, Mazeaud M, Pernollet M G, Ben Ishay D, Devynck M A
Pharmacology, Necker Medical School, CNRS 6167, Paris, France.
Life Sci. 1991;49(26):1973-7. doi: 10.1016/0024-3205(91)90639-s.
Na+ ions, which can play a pathogenic role in the development of high blood pressure, have been reported to regulate membrane enzymatic activities, receptor-ligand interaction and coupling of G-protein receptors to their effectors. This study was designed to investigate the in vitro effects of Na+ ions on membrane dynamic properties. The fluorescence anisotropy values of TMA-DPH (trimethylamino-diphenylhexatriene, probe selectively incorporated into the outer leaflet of the plasma membrane) was evaluated in platelets and erythrocytes of sodium-dependent hypertension-prone and -resistant rats of the Sabra Strain. Whereas no difference was observed between the 2 strains, TMA-DPH anisotropy was found to be strongly influenced in platelets by external Na+ ions. In the absence of external Na+, TMA-DPH anisotropy increased in human and rat platelets. In contrast, Na+ ions did not affect the anisotropy when the probe was inserted into erythrocyte ghosts. This indicates that Na+ ions can acutely regulate order parameter and microviscosity of platelet plasma membrane in the regions explored by the probe.
据报道，钠离子在高血压的发展过程中可能起到致病作用，它能调节膜酶活性、受体 - 配体相互作用以及G蛋白受体与其效应器的偶联。本研究旨在探讨钠离子对膜动力学特性的体外影响。在易患和抗钠依赖性高血压的Sabra品系大鼠的血小板和红细胞中，评估了TMA - DPH（三甲基氨基 - 二苯基己三烯，一种选择性掺入质膜外小叶的探针）的荧光各向异性值。虽然在这两个品系之间未观察到差异，但发现血小板中的TMA - DPH各向异性受到外部钠离子的强烈影响。在没有外部钠离子的情况下，人和大鼠血小板中的TMA - DPH各向异性增加。相反，当探针插入红细胞影时，钠离子不影响各向异性。这表明钠离子可以急性调节探针所探测区域内血小板质膜的序参数和微粘度。
