[The effect of streptokinase on the development of rat cerebral cortex cells in vitro].

The aim of this study was to determine the effect of streptokinase (SK) on the ultrastructure of cellular elements in the cerebral cortex of newborn rats in vitro. Three series of cell cultures grown on DMEM were used, including those grown on the medium enriched with 15% fetal calf serum (control 1), cultures transferred to the depleted medium containing only 0.5% of this serum (control 2), and the experimental cultures, to which SK (2000 IU/ml) was added. Addition of SK to the medium prevented a reduction of the viability of mature (14 days) dissociated neocortical cell culture from 1-2-day-old rats, induced by a transfer of the culture to a blood serum protein-deficient medium. In a 7-day culture SK potentiated the decrease in the cell viability. In organotypical cultures, with the use of electron microscopy, it was found that SK in concentration used prevented the development of destructive changes in astrocytes, oligodendrocytes, and neurons of explants, induced by a deficit in serum proteins. The neurons contained numerous mitochondria, some of which had only a few cristae. Signs of destruction were observed only in neuronal nuclei. After exposure to SK for 48 hours an activation of oligodendrocytes (containing numerous myelin bodies) was noted which was accompanied by astrocyte disintegration (with hyperchromatic nuclei in the remaining cells). The neurons were resistant to SK exposure.