[Spatial and temporal heterogeneity of pH values in lysosomes from different types of cells cultured in situ]

Distinct variety of the pH value, at the ranges of pH 4.5-7.0, was found in lysosomes. Small lysosomes exhibited lower pH values as compared with large organelles. These lysosomes were measured in cultures of normal cells (hamster fibroblasts, pig embryonal kidney cells, primary culture of chicken embryonal fibroblasts) and of tumoral cells (neurinoma of rat trigeminal ganglion). Studies of individual lysosomes demonstrated that temporal alterations in the pH value reached up to 1.5 un of the pH period 15-45 min. Distinct space-temporal heterogeneity of the cellular lysosomal apparatus in the pH value enabled to create optimal conditions for enzymatic systems catalyzing hydrolysis of various macromolecules. The mean values of pH were very similar in all the cultivated cells studied, within ranges of pH 5.5-5.8, which appears to depend on the similarity of functions of the lysosomal apparatus in the cells of various classes.