EFFECT OF PENTOBARBITAL ON MITOCHONDRIAL SYNTHESIS IN CULTURED GLIAL-CELLS

Abstract— Primary cultures of glial cells prepared from brains of newborn rats were grown for 1 week and then exposed to 5 × 10−4m‐pentobarbital (PB) for 4 weeks. Compared with glial cells grown in drug‐free medium throughout, exposure to PB significantly increased hexokinase activity, primarily in its mitochondrial form. Furthermore, cellular protein and RNA concentrations were significantly higher in barbiturate‐cultivated than in control cells. Pulse labelling with [3H]thymidine after 4 weeks of PB exposure resulted in a significant increase (332%) in 3H incorporation into mitochondrial DNA while 3H incorporation into nuclear DNA was reduced by 58%. In addition, there was a time dependent increase in the size and number of mitochondria as determined in electron micrographs. These results are interpreted to reflect an increased mitochondrial metabolism in glial cells after chronic exposure to the barbiturate and may constitute a compensatory mechanism to the depressant action of this drug. Copyright © 1979, Wiley Blackwell. All rights reserved