AI Article Synopsis
- Cytochemical studies revealed that lymphocytes from blood showed minimal ATPase activity when uncultured, but this activity significantly increased during cellular transformation.
- In fully transformed lymphocytes, ATPase activity was intense and localized in a distinct area of the cytoplasm, especially visible in stained samples.
- The ATPase activity had an optimal pH of 8.5 to 9.5, was stimulated by calcium and magnesium, and was inhibited by certain substances like p-chloromercuribenzoate, while oligomycin appeared to enhance the reaction.
Article Abstract
Cytochemical investigations of ATPase activity were performed on lymphocytes isolated from peripheral blood and activated in vitro by phytohaemagglutinin or by the two-way mixed lymphocyte reaction. Uncultured lymphocytes showed very little activity localized in small granules. The activity increased markedly during transformation. In fully transformed and actively proliferating cells, the ATPase activity was intense and localized in a crescentic perinuclear area of cytoplasm which was pale-staining and vesicular in Giemsa-stained preparations. In mitotic cells, the activity was in discrete granules or elongated structures suggestive of mitochondria, scattered throughout the cytoplasm. The ATPase activity had a pH optimum of 8.5 to 9.5 and was strongly inhibited at pH 7.5. The activity was stimulated by Ca2+ and Mg2+ and was inhibited by p-chloromercuribenzoate but not by oligomycin, which appeared to enhance the reaction. Lead nitrate at a concentration of 3 mM did not inhibit the reaction.
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