Calcium-related structural organization of glial cells cytoskeleton in vitro

Experiments were performed on tissue culture of astrocytomas obtained at surgery. Dispersed cell cultures were used in this study growing directly on glass slides. In the course of experiments calcium ions (Ca2+) were added to extracellular fluid in the following concentrations: 3mg/ml--7.5 x 10(-2)M, 6mg--1.5 x 10(-1)M, and 12 mg--3.5 x 10(-1)M. No significant changes were observed in cells cultivated with two concentrations of calcium; 3 mg/ml and 6 mg/ml, only at the concentration of 12 mg/ml a disaggregation of microfilaments was revealed with the Coommassie blue R 250 staining. Introduction into the incubation medium of the ionophore A 23187 introduces dearrangement of microfilaments at all concentration of calcium used in the experiment. Additionally at the highest concentration of calcium that is at 12 mg/ml, the enhancement of staining density and thickness of glial ectoplasm could be observed and the aggregation microfilaments to thick boundles paralleled by the retraction of cell processes. It is concluded that glial cells show similar changes at elevated calcium ion concentrations with the ionophore added as observed in other cell types.