[Cytochemical studies of primary granules in rat neutrophils: an electron microscope study].

Cytochemical investigations were carried out on primary granules in neutrophils in rats. For this purpose reaction for acid phosphatase and then using the same preparations of bone marrow peroxidase activity was determined. Peroxidase activity was demonstrated in all granules of first order (primary), but only in a part of them the activity of acid phosphatase was present. These granules are, most probably, lysosomes containing peroxidases apart from hydrolases.