Chandler D E
J Cell Sci. 1984 Dec;72:23-36. doi: 10.1242/jcs.72.1.23.
Eggs of the purple sea-urchin, Strongylocentrotus purpuratus, were fertilized and fixed with 2% glutaraldehyde at various stages during cortical granule exocytosis. Fixation resulted in membrane blebs being formed precisely at the point of incipient granule fusion. These blebs pinched off to form the membranous vesicles frequently seen in exocytic pockets and in the perivitelline space. In contrast, eggs that were fixed with osmium tetroxide or were quick-frozen without chemical fixation, showed no signs of bleb or vesicle formation. Rather, fusion of each granule appeared to begin at a single minute pore, 30-50 nm in diameter, which then enlarged. We suggest that formation of blebs during glutaraldehyde fixation is an artifact that is caused by a highly localized and transient increase in membrane mobility. Normally, this increased mobility facilitates fusion of granule and plasma membranes, but in the presence of glutaraldehyde it leads to large-scale distortions of these fusing membranes.
紫色海胆（紫海胆）的卵在皮质颗粒胞吐作用的不同阶段受精并用2%戊二醛固定。固定导致在颗粒开始融合的点精确形成膜泡。这些膜泡 pinched off（此处原文有误，推测为pinched off，意为“掐断”）形成在胞吐小袋和卵周隙中常见的膜性小泡。相比之下，用四氧化锇固定或未经化学固定快速冷冻的卵，没有显示出膜泡或小泡形成的迹象。相反，每个颗粒的融合似乎始于一个直径为30 - 50纳米的单个微孔，然后该微孔扩大。我们认为戊二醛固定过程中膜泡的形成是一种假象，是由膜流动性高度局部化和短暂增加引起的。正常情况下，这种增加的流动性促进颗粒膜与质膜的融合，但在戊二醛存在的情况下，它会导致这些融合膜的大规模变形。
