Substitution of cassava starch for polyvinyl alcohol in the histochemical stain for glucose-6-phosphate dehydrogenase in animal tissues

Abstract

The histochemical localisation of glucose-6-phosphate dehydrogenase (G-6-PD) in tissues, using aqueous media is problematic because more than 90% of the activity of this enzyme is lost in the media, thereby giving a value that is much less than the real value. The gel method was tried to solve this problem but with little success. The improved method by Negi and Stephens, which incorporated 22% polyvinyl alcohol (PVA) in the incubation media, was an improvement in the histochemical demonstration of G-6-PD activity in tissues. In this investigation, we used 5% cassava starch, instead of PVA. Result showed improved localisation of the activity of G-6-PD in the liver and testis of Sprague Dawley rats which was statistically better than the Negi and Stephens' method. We conclude that cassava starch is a better, safer and cheaper substitute to PVA, in the localisation of the activity of G-6-PD in animal tissue.