[On the cytochemical demonstration of glycogen in neutrophil granulocytes: periodic acid-Schiff reaction and diastase (amylase) digestion test (author's transl)].

The results of the present investigation indicate clearly that treatment of blood smears with diastase resp. amylase is unsuitable to identify glycogen in neutrophil granulocytes. This may be attributed to the contamination with proteases of commonly used preparations of diastase resp. amylase. Thus strong PAS-reactive material which presents most probably not glycogen but PAS-positive glycoproteins may be eliminated by the proteolytic activity of the contaminants. - In detail it has been shown that susceptibility resp. resistance of the PAS-positive material against treatment with diastase resp. amylase is highly dependent on both type of fixation and fixation time: Fixation with formol free absolute alcohol (ethanol, methanol), leads also after prolonged fixation time to a complete loss of PAS-staining after preliminary treatment with diastase resp. amylase. On the other side after fixation with formol containing fixatives (for example formol/ethanol and acetic acid/formol/ethanol) only after short term fixation practically a complete loss of PAS-staining material is observed. However, after long term fixation more or less complete resistance of the PAS-stainable material against treatment with diastase resp. amylase has been found.