Effect of corticosterone treatment on mitochondrial oxidative energy metabolism in developing rat brain

Effects of "acute" and "chronic" corticosterone treatment on energy metabolism in brain mitochondria from rats belonging to various age groups were examined. Both acute and chronic treatments resulted in significant reduction in the state 3 respiration rates and in the lowering of ADP/O ratios with the various substrates tested. The effects were age and substrate specific and in general the extent of uncoupling was greater in chronically treated rats. Corticosterone treatments also resulted in site-specific uncoupling in an age-dependent manner. The overall effect of corticosterone treatments was lowering of ADP phosphorylation rates, thereby causing an energy deficit. The effects on dehydrogenase activities were of a variable nature. Our results suggest that energy deficits following corticosteroid treatment may be an underlying cause for impaired brain development reported by earlier researchers.