Ohga S, Hamamoto K, Kitajima H, Nagata H, Nomura S, Kimura T, Fujitake H, Kokawa T, Yasunaga K
First Department of Internal Medicine, Kansai Medical University, Osaka, Japan.
Int J Hematol. 1991 Aug;54(4):331-9.
Transformation upon mild stimulation and the ultrastructure of blood platelet alpha-granules were examined using cryo-ultramicrotomy. An ultrastructural study found not only round, but also elongated and drumstick-shaped alpha-granules and rod-like structures protruding from round alpha-granules. Some elongated alpha-granules showed distinctive cross-striations in the short axis with a periodicity in the order of 19-22 nm. Gold particle-labeled fibrinogen (Fbg) was observed on elongated alpha-granules having cross-striations. Electron-dense nucleoids were observed on some round alpha-granules. An electron-dense nucleoid, intermediate zone, and an electron-lucent matrix were noted in round alpha-granules by gold particle-labeled Fbg in the intermediate zone. Gold particle-labeled von Willebrand factor (vWF) was observed in alpha-granules except in nucleoid zones. Labeling for Fbg was also observed in rod-like structures protruding from round alpha-granules. Gold particle-labeled glycoprotein (GP)IIb/IIIa complex was observed on the inner face of alpha-granule membranes. A few elongated and drumstick-like alpha-granules were found on freshly fixed platelets. Elongated alpha-granules were only found in a small percentage of washed and collagen-stimulated platelets. Cryo-ultramicrotomy is useful for examination of the distribution of intracellular antigens.
使用冷冻超薄切片术检查了轻度刺激后的转化情况以及血小板α颗粒的超微结构。一项超微结构研究发现，α颗粒不仅呈圆形，还呈细长形和鼓槌形，并且有从圆形α颗粒伸出的杆状结构。一些细长的α颗粒在短轴上显示出独特的横纹，其周期约为19 - 22纳米。在具有横纹的细长α颗粒上观察到金颗粒标记的纤维蛋白原（Fbg）。在一些圆形α颗粒上观察到电子致密核仁。通过中间区域的金颗粒标记Fbg，在圆形α颗粒中注意到电子致密核仁、中间区域和电子透明基质。除核仁区域外，在α颗粒中观察到金颗粒标记的血管性血友病因子（vWF）。在从圆形α颗粒伸出的杆状结构中也观察到Fbg标记。在α颗粒膜的内表面观察到金颗粒标记的糖蛋白（GP）IIb/IIIa复合物。在新鲜固定的血小板上发现了一些细长和鼓槌状的α颗粒。细长的α颗粒仅在一小部分洗涤过的和经胶原刺激的血小板中发现。冷冻超薄切片术对于检查细胞内抗原的分布很有用。
