Amsterdam A, Schramm M
J Cell Biol. 1966 May;29(2):199-207. doi: 10.1083/jcb.29.2.199.
Fixation by osmium tetroxide and glutaraldehyde of zymogen granules isolated from rat parotid and pancreas was investigated. Protein determinations showed that osmium tetroxide caused rapid release of most of the soluble protein of the granule during fixation in buffered isotonic sucrose. Such granules when examined in the electron microscope after shadow casting appeared quite flat, indicating that most of the contents had indeed been removed. Numerous damaged membranes of the granules were also observed. In contrast, zymogen granules fixed by glutaraldehyde and shadow cast essentially retained the spherical shape and the protein contents. The application of the shadow-casting technique in quantitative studies on the protein content of zymogen granules is discussed.
对从大鼠腮腺和胰腺分离出的酶原颗粒用四氧化锇和戊二醛进行固定的情况进行了研究。蛋白质测定表明，在等渗蔗糖缓冲液中固定时，四氧化锇会导致颗粒中大部分可溶性蛋白质迅速释放。经投影后在电子显微镜下检查时，这类颗粒显得相当扁平，这表明大部分内容物确实已被去除。还观察到颗粒的许多受损膜。相比之下，用戊二醛固定并投影的酶原颗粒基本保持球形和蛋白质含量。讨论了投影技术在酶原颗粒蛋白质含量定量研究中的应用。
