Maurício Ana C, Penque D, Amaral M D, Ferreira K T
Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto.
Acta Med Port. 2004 Nov-Dec;17(6):427-34. Epub 2005 Jan 18.
Tall columnar epithelial (TCE) cells can be obtained by a non-invasive procedure through brushing the inferior turbinate and the adjacent lateral nasal wall. Here, we present results from the functional study of epithelial cells, thus obtained by using the patch-clamp technique. By patch-clamping the sub-apical region of TCE cells, we were able to identify at least three different groups of Cl- channels, namely: a) one with large conductance, rectifying, which was the most frequently found type of Cl- channel; b) a second type of small conductance, activated by cAMP and IBMX, in excised inside-out patches and voltage independent; c) a third type with a conductance around 25 pS, voltage independent, with a linear IV relationship, that could be observed in the excised inside-out configuration. The study of CFTR Cl- channel and its role in airway cell physiology has generally been conducted in cultured cells, most of which not polarized. This experimental work using freshly obtained TCE cells from the nasal epithelium, demonstrates that such cells may be one valid tool to study Cl- channels (most probably ORCC and CFTR Cl- channels) as a model for the lower respiratory epithelium.
高柱状上皮（TCE）细胞可通过刷取下鼻甲和相邻的鼻侧壁这一非侵入性操作获得。在此，我们展示了通过使用膜片钳技术从这些细胞获得的上皮细胞功能研究结果。通过对TCE细胞的顶端下区域进行膜片钳记录，我们能够识别出至少三组不同的氯离子通道，即：a）一种具有大电导、整流性，是最常见的氯离子通道类型；b）第二种是小电导类型，在切除的内向外膜片中由cAMP和异丁基甲基黄嘌呤激活，且与电压无关；c）第三种电导约为25 pS，与电压无关，具有线性电流-电压关系，可在切除的内向外构型中观察到。关于囊性纤维化跨膜传导调节因子（CFTR）氯离子通道及其在气道细胞生理学中的作用的研究通常是在培养细胞中进行的，其中大多数细胞没有极化。这项使用从鼻上皮新鲜获取的TCE细胞的实验工作表明，此类细胞可能是作为下呼吸道上皮模型研究氯离子通道（很可能是外向整流性氯离子通道和CFTR氯离子通道）的一种有效工具。
