MORPHOLOGICAL FACTORS INFLUENCING TRANS-EPITHELIAL PERMEABILITY - MODEL FOR RESISTANCE OF ZONULA-OCCLUDENS
MORPHOLOGICAL FACTORS INFLUENCING TRANS-EPITHELIAL PERMEABILITY - MODEL FOR RESISTANCE OF ZONULA-OCCLUDENS
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DOI：
10.1007/bf01870332
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发表时间：
1978-01-01
影响因子：
2.4
通讯作者：
CLAUDE, P
中科院分区：
文献类型：
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作者：
CLAUDE, P
上皮细胞在它们的顶面由闭合小带连接。Claude和Goodenough证明了冷冻断裂制备中所见的闭合小带结构与几种简单上皮细胞的被动电渗透性之间的相关性。在高跨上皮阻力的上皮中，闭锁小带由许多股组成。在低跨上皮阻力的上皮细胞中，闭锁小带大大减少，有时仅由1条链组成。在一些简单的上皮细胞中，闭锁小带的结构主要负责跨上皮电导的大小。推导出将跨上皮连接电阻与连接链数量相关的方程：R = Rminp-n，其中R是闭合小带的跨上皮电阻，Rmin是连接的最小电阻（当闭合小带中没有链时），p是给定链打开的概率，n是连接中的链数量。使用已发表的不同上皮细胞的R和n的实验值，p的计算值高达0.4，这表明闭锁小带中的链是非常不稳定的。还考虑了与跨上皮渗透性相关的其他形态学参数，例如细胞间隙的宽度和深度以及上皮细胞本身的大小。[This模型基于来自膀胱、肠和肾小管的上皮细胞。
Epithelial cells are joined at their apical surfaces by zonulae occludentes. Claude and Goodenough demonstrated a correlation between the structure of the zonula occludens as seen in freeze-fracture preparations and the passive electrical permeability of several simple epithelia. In epithelia with high transepithelial resistance, the zonula occludens consisted of many strands. In epithelia with low transepithelial resistance the zonula occludens was much reduced, sometimes consisting of only 1 strand. In a number of simple epithelia the structure of the zonula occludens is largely responsible for the magnitude of transepithelial conductance. An equation is derived relating transepithelial junctional resistance to the number of junctional strands: R = Rminp-n where R is the trn transepithelial resistance of the zonula occludens, Rmin is the minimum resistance of the junction (as when there are no strands in the zonula occludens), p is the probability a given strand is open and n is the number of strands in the junction. Using published experimental values of R and n for different epithelia, the calculated value of p was as high as 0.4, which suggests that the strands in the zonula occludens are remarkably labile. Other morphological parameters relevant to transepithelial permeability are also considered, such as the width and depth of the intercellular spaces and the size of the epithelial cells themselves. [This model is based on epithelium derived from the bladder, intestine and kidney tubules.].