Nermut M V, Williams L D, Stamatoglou S C, Bissell D M
Eur J Cell Biol. 1986 Oct;42(1):35-44.
Rat hepatocytes obtained by means of liver perfusion with collagenase were allowed to spread on type IV collagen coated coverslips for 20 h. Interference reflection microscopy revealed a peripheral ring of dark spots. Carbon replicas of ventral membranes left attached to coverslips after lysis and squirting provided high resolution information on the ultrastructure of the protoplasmic surface. Correlative light and electron microscopy of the same ventral membrane showed that the area of the peripheral 'adhesion annulus' was rich in clathrin-coated structures (sheets, pits and vesicles). In vertical thin sections of hepatocyte monolayers numerous small smooth vesicles were observed piled up below the peripheral portion of the cell. These findings suggest high cytotic activity at the cell periphery during spreading. No bundles of microfilaments were observed in cells after squirting or in sections, but a ring of filaments at the cell periphery could be seen in many cells in whole mount preparations after treatment with Triton X-100. The absence of microfilaments associated with the points of adhesion indicates a cytoskeleton independent adhesion mechanism in hepatocytes during the first 20 h of spreading.
通过用胶原酶灌注肝脏获得的大鼠肝细胞，使其在包被有IV型胶原的盖玻片上铺展20小时。干涉反射显微镜显示有一圈外周的暗斑。在裂解和喷射后留在盖玻片上的腹侧膜的碳复型提供了关于原生质表面超微结构的高分辨率信息。对同一腹侧膜进行的相关光学和电子显微镜观察表明，外周“粘附环”区域富含网格蛋白包被结构（片层、小窝和小泡）。在肝细胞单层的垂直薄切片中，观察到许多小的光滑小泡堆积在细胞外周部分下方。这些发现表明铺展过程中细胞外周具有高胞吞活性。在喷射后或切片中的细胞中未观察到微丝束，但在用Triton X-100处理后的整装标本中，许多细胞的细胞外周可见一圈细丝。与粘附点相关的微丝的缺失表明在铺展的最初20小时内，肝细胞中的粘附机制独立于细胞骨架。
