Cytophotometric determination of non-heme iron in hepatocytes. II. Effect of fixation on the cell iron content

The study deals with the effect of different fixatives, such as absolute methanol, 96% ethanol, 10% buffered neutral formalin, as well as mixtures: methanol-formalin-acetic acid and ethanol-formalin-acetic acid (Tellesnitsky's solution) on preservation of iron in isolated hepatocytes of rats on a diet with addition of 2% carbonyl iron. The iron preservation in cells, on application of different fixatives and performance of Perls' reaction, was evaluated by the intensity of cell staining that was measured using cytospectrophotometer. The best preservation of iron in cells has been achieved when using alcohol fixatives only. Fixation of preparations with the methanol-formalin-aceticacid mixture also produced no decrease in the iron content in hepatocytes, however, morphology of the stained cells was much worse than after methanol and ethanol fixation. Fixation with Tellesnitsky's solution resulted in a 36% reduction of the cellular iron content, whereas fixation with 10% neutral formalin reduced iron content by 58%, as compared with methanol fixation. A prolongation formalin fixation from 10 min to 24 hr had no effect on the intensity of Perls' reaction.