1984 Volume 23 Issue 1 Pages 16-23
Lactate dehydrogenase (LDH) is applied to cytodiagnosis of the lung cancer by enzyme histochemistry. As intracellular LDH is thought to be influenced by some factors thought bronchial passway, differences between sputum and brushing are studied and analyzed on serum LDH and LDH isozyme patterns.
The LDH activity are visualized by conversion of Nitro-Blue-Tetrazolium into insoluble formazan (2H). For this purpose, the Urea Inhibition Test is done by 2.6 mol urea in the staining solution for identification of the LDH-M subunits, compared with loss of LDH activity and total LDH.
By the LDH stain, diformazan-positive normal cells have almost same activities in sputum and brushing material. And they do not show loss of LDH activity by the Urea Inhibition test. Diformazan-positive cancer cells in brushing materials show higher activity than sputum and they show loss of LDH activity by the Urea Inhibition test.
The LDH-M subunits is thought to be dominant in cancer cells in sputum and brushing specimen. Intracellular LDH of cancer cells are not so influenced through bronchial passage and it is recognized as a good method of cytodiagnosis of sputum specimen in lung cancer.
