Effects of barbiturates on energy and intermediary metabolism in cultured astrocytes.

Effects of barbiturates on utilization of the two substrates, glucose and glutamate, were studied in astrocytes in primary cultures. Carbon dioxide formation from glucose was under ordinary conditions not affected by barbiturates but in the presence of 10 microM malate there was a potassium-induced stimulation (20-25%) which was significantly (P less than 0.001) inhibited (30-35%) by pentobarbital (0.5 mM). Glutamate oxidation was not enhanced by excess potassium but there was a distinct dose-dependent reduction in the presence of pentobarbital. In contrast, pentobarbital or phenobarbital had no effect on the formation of glutamine from glutamate.