Guinea pig testes were processed for electron microscopy by prefixing in phosphate-buffered aldehyde and postfixing in 1% OsO4 plus 0.05 M potassium ferricyanide [(K3Fe(CN)6)]. The K3Fe(CN)6 enhanced the staining of glycogen, which was located predominantly in the Sertoli cells, and decreased the staining of ribosomes. The K3Fe(CN)6 also selectively stained some of the small vesicles associated with the forming faces of spermatid Golgi apparatus, the nuclear envelope under the acrosome, and the ground substance of spermatid and spermatozoa mitochondria. This last staining reaction was subdued or absent from spermatocytes, spermatogonia, Sertoli cells, and Leydig cells. © 1980, Academic Press, Inc.. All rights reserved.
Mollenhauer, H. H., & Droleskey, R. E. (1980). Some specific staining reactions of potassium ferricyanide in cells of guinea pig testes. Journal of Ultrastructure Research, 72(3), 385–391. https://doi.org/10.1016/S0022-5320(80)90073-8