Holland V F, Zampighi G A, Simon S A
Department of Neurobiology, Duke University Medical Center, Durham, North Carolina 27710.
J Comp Neurol. 1989 Jan 1;279(1):13-27. doi: 10.1002/cne.902790103.
The localization and structure of intercellular junctions and barriers in the extragemmal epithelium of canine fungiform papillae were determined by using both morphological and electrophysiological methods. Gap junctions were located in all epithelial strata with the exception of the stratum corneum, suggesting that the epithelium functions as a syncytium. The extracellular space of the stratum corneum was composed of a discontinuous, three-dimensional network of tight junctions, modified desmosomes, and lamellar bodies. A zonula occludens, which stops the penetration of lanthanum, is present in the uppermost layer of the stratum granulosum. In freeze-fracture replicas, tight junctions appear as extended networks of ridges of variable thickness on the PF fracture face and complementary grooves on the EF fracture face. The relatively high resistance pathway resulting from the layers of corneocytes and networks of tight junctions and lamellar bodies in the stratum corneum is bypassed by the low-resistance pathway provided by the taste pore.
采用形态学和电生理学方法，确定了犬菌状乳头味蕾外上皮细胞间连接和屏障的定位与结构。除角质层外，所有上皮层均有缝隙连接，这表明上皮组织起到了合胞体的作用。角质层的细胞外空间由紧密连接、改良桥粒和板层小体组成的不连续三维网络构成。在颗粒层的最上层存在阻止镧渗透的紧密连接带。在冷冻蚀刻复制品中，紧密连接在PF断裂面上表现为厚度可变的嵴的扩展网络，在EF断裂面上表现为互补的凹槽。角质层中角质形成细胞层以及紧密连接和板层小体网络所形成的相对高电阻通路，被味孔提供的低电阻通路所绕过。
