Chan H C, Nelson D J
Department of Medicine, University of Chicago, IL 60637.
Science. 1992 Jul 31;257(5070):669-71. doi: 10.1126/science.1379742.
A chloride (Cl-)-dependent, nonselective cation conductance was activated during cellular shrinkage and inhibited during cellular swelling or by extracellular gadolinium. The shrinking-induced, nonselective cation conductance and the swelling-induced anion conductance appear to function in the regulation of cell volume in airway epithelia. The shrinking-induced cation conductance had an unusual dependence on Cl-: partial replacement of extracellular Cl- with aspartate reduced the magnitude of the shrinking-enhanced current without accompanying changes in the reversal potential. The Cl- dependence of the nonselective cation conductance could provide a mechanism that tightly regulates Cl- secretion and sodium reabsorption in cells under osmotic stress.
一种依赖氯化物（Cl-）的非选择性阳离子电导在细胞收缩时被激活，在细胞肿胀时或被细胞外钆抑制。收缩诱导的非选择性阳离子电导和肿胀诱导的阴离子电导似乎在气道上皮细胞体积调节中起作用。收缩诱导的阳离子电导对Cl-有异常依赖性：用天冬氨酸部分替代细胞外Cl-可降低收缩增强电流的幅度，而反转电位无伴随变化。非选择性阳离子电导对Cl-的依赖性可为在渗透应激下紧密调节细胞中Cl-分泌和钠重吸收提供一种机制。
