Joiner C H
Department of Pediatrics, University of Alabama School of Medicine, Birmingham 35294.
Pediatr Res. 1988 Oct;24(4):495-8. doi: 10.1203/00006450-198810000-00016.
The abnormalities in ion transport in cystic fibrosis (CF) respiratory and sweat duct epithelia have prompted studies of ion permeability in CF red blood cells (RBC) although previous reports have been contradictory. In this study, the kinetic characteristics of the three major cation transport systems in RBC were evaluated by measuring rubidium (Rb) uptake at various external Rb concentrations. The maximal velocity and affinity for external Rb (K1/2) of the NaK pump were normal in CF RBC, as were the maximal velocity and Km for Rb of the NaK cotransport system. Residual (ouabain and bumetanide insensitive) Rb uptake, and steady state RBC Na and K contents were also normal. These data indicate the NaK pump and cotransport system do not exhibit primary or secondary perturbations in CF RBC, and suggest that the noncarrier-mediated membrane permeability to cations is also normal in these cells.
尽管先前的报告相互矛盾，但囊性纤维化（CF）呼吸道和汗腺导管上皮细胞中的离子转运异常促使人们对CF红细胞（RBC）的离子通透性进行研究。在本研究中，通过测量不同外部铷（Rb）浓度下的铷摄取量，评估了RBC中三种主要阳离子转运系统的动力学特征。CF RBC中钠钾泵对外部Rb的最大速度和亲和力（K1/2）正常，钠钾共转运系统对Rb的最大速度和Km也正常。残余（哇巴因和布美他尼不敏感）的Rb摄取以及RBC钠和钾的稳态含量也正常。这些数据表明，CF RBC中的钠钾泵和共转运系统未表现出原发性或继发性扰动，并提示这些细胞中阳离子的非载体介导的膜通透性也正常。
