Histochemical Demonstration of Succinic Dehydrogenase in Ascites Tumor Cells

Abstract

Fresh undiluted tumor ascites (0.05 ml) withdrawn from the peritoneal cavity was placed immediately in a centrifuge tube containing 2.0 ml of an aqueous mixture prepared with 1 part each of the following solutions: 1% neotetrazolium chloride, 0.2 [image] sodium succinate and 0.1 [image] phosphate buffer, pH 7.4. The tube was incubated for 2 hr. at 37[degree]C and centrifuged for 3 min. at 700 rev/ min. The precipitate was washed with 0.85% saline solution and subsequently fixed with neutral 10% formalin for 10 min. After centrifu-gation, smears or squash preparations of the precipitate were prepared. Succinic dehydrogenase activity was demonstrated very distinctly and uniformly by the granular deposition of a deep purple pigment intra-cellularly.