USE OF PRIMARY CULTURES AND CONTINUOUS CELL-LINES TO STUDY EFFECTS ONASTROCYTIC REGULATORY FUNCTIONS

1. Current opinions on the mechanisms for glutamate-mediated neurotoxi city are reviewed. The protective role of astrocytic high-affinity glu tamate transport is also discussed. 2. Low-density seeding of primary astrocytes from rat hemispheres was found to result in the development of reactive-like astrocytes. Typical glial signs of amyotrophic later al sclerosis (ALS) could not be induced in astrocyte cultures by serum from ALS-patients. 3. Glutamate(100 mu mol/L) was found to induce an increase in respiratory activity in primary cultures of astrocytes. Th is stimulation appeared to be related to the co-transport of Na2+ with glutamate and a resulting activation of Na2+/K+-ATPase. Both basal re spiration and glutamate-stimulated oxygen consumption was inhibited by organic solvents. 4. Preliminary results show that heavy metals cause an increase in the mitochondrial DNA content at concentrations that h ave no effect on growth rate or morphology in a glial cell line. This increase was accompanied by an inhibition of oxygen consumption and an increased production of lactate at unaltered ATP levels.