Ainsworth S K
J Histochem Cytochem. 1977 Nov;25(11):1254-9. doi: 10.1177/25.11.915245.
A simple method has been developed whereby polymers of polyvinylpyrrolidone and dextran can be visualized at the ultrastructural level by postfixing tissue with osmium tetroxide partially reduced by potassium ferrocyanide. Further enhancement of polymer electron opacity is obtained by counterstaining thin sections with bismuth subnitrate chelated by alkaline tartrate. These tracers remain adequately dispersed in serum and, depending on molecular size and concentration, are easily detected at the ultrastructural level within vascular lumena, basement lamina, apical vacuoles of proximal and distal tubules and endothelial vesicles. This technique offers the potential of studying nephron and cell permeability with families of tracers, the members of which are similar in chemical affinities, charge density and molecular shape.
已开发出一种简单方法，通过用亚铁氰化钾部分还原的四氧化锇对组织进行后固定，可在超微结构水平观察到聚乙烯吡咯烷酮和葡聚糖的聚合物。用酒石酸盐螯合的次硝酸铋对薄切片进行复染，可进一步增强聚合物的电子不透明度。这些示踪剂在血清中能充分分散，根据分子大小和浓度，很容易在超微结构水平在血管腔、基膜、近端和远端小管的顶端液泡以及内皮小泡中检测到。该技术提供了用一系列示踪剂研究肾单位和细胞通透性的潜力，这些示踪剂的成员在化学亲和力、电荷密度和分子形状方面相似。
