A quantitative study of the validity of the histochemical demonstration for pyridine nucleotide-linked dehydrogenases

Summary A quantitative histochemical and biochemical study has been made of the loss of pyridine nucleotide-linked dehydrogenases from frozen histological sections of rat liver. Glucose-6-phosphate, 6-phosphogluconate and lactate dehydrogenases were lost rapidly from the sections during incubation in the histochemical medium, but -OH-butyrate dehydrogenase was lost at a much slower rate. It was shown that a dehydrogenase reaction can occur in a section lacking that particular dehydrogenase if the section is incubated in the presence of another containing the dehydrogenase. The validity of the tetrazolium reaction for demonstrating pyridine-nucleotide-linked dehydrogenases is considered in the light of these results.