Identification of active cell in potassium transporting epithelium.
Identification of active cell in potassium transporting epithelium.
复制标题
钾转运上皮中活性细胞的鉴定。
DOI：
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发表时间：
1978
影响因子：
2.8
通讯作者：
W. Harvey
中科院分区：
文献类型：
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作者：
J. T. Blankemeyer;W. Harvey
上皮细胞离子转运调节细胞内环境，调节细胞内环境，使真核生物的进化成为可能。运输过程的分析要求离子在上皮细胞中主动运输时所采取的路线是已知的。该路线可以通过定位离子泵电动和通过测量运输池大小动力学提供的上皮结构是足够简单，使结果被解释在细胞方面。钾是积极运输的鳞翅目昆虫中肠的路线证明了在这里由电气和动力学分析相结合。两种细胞，杯状细胞和柱状细胞，是由他们的电特性区分。杯状细胞是钾离子转运的活跃场所，钾离子泵位于杯状细胞的顶膜。杯状细胞与柱状细胞电耦合时，只有中肠已被隔离从饮食饲养的幼虫短路。这一结果的一个推论是，当杯状细胞与柱状细胞不偶联时，参与运输的钾池的大小应该很小，而当它们偶联时，钾池的大小应该变大。这一推论已被证实的直接测量的运输池使用同位素示踪动力学分析。这是第一次，负责主动离子运输的多态性组织中的细胞类型已被确定直接通过生理手段。
Epithelial ion transport regulates the environment of cells and modulates the environment inside them, making possible the evolution of eukaryotic organisms. Analysis of the transport process requires that the route taken by ions as they are actively transported across epithelia be known. The route can be determined by locating ion pumps electrically and by measuring transport pool sizes kinetically provided that the epithelial structure is simple enough to enable the results to be interpreted in cellular terms. The route by which potassium is actively transported across the lepidopteran midgut is demonstrated here by a combination of electrical and kinetic analyses. Two sorts of cells, goblet and columnar cells, are distinguished by their electrical properties. The goblet cell is identified as the site of active potassium transport, the pump being localized in its apical membrane. The goblet cells are electrically coupled with columnar cells only when midguts that have been isolated from diet-reared larvae are short circuited. A corollary to this result is that the size of the pool of potassium which is involved in transport should be small when the goblet cells are not coupled with columnar cells and should become large when they are coupled. This corollary has been confirmed by direct measurement of the transport pools using isotope tracer kinetic analysis. This is the first time that the cell type responsible for active ion transport in a polymorphic tissue has been identified directly by physiological means.