Maturation of Potassium-Stimulated Respiration in Rat Cerebral Cortical Slices

Abstract: Maximal dinitrophenol-stimulated respiration and K⁺-stimulated respiration were measured polarographically in cerebral cortical slices taken from rats aged 2–60 days. Increasing K⁺ concentrations produced an increase in respiration in slices from animals aged 15 days and older, but not in slices from animals aged 10 days and younger. Dinitrophenol-stimulated respiration, or the maximal respiratory capacity of the tissue, showed a similar increase between 10 and 15 days of age. At each age the maximal respiratory capacity was 6–8 ng at 0/mg protein min greater than the maximal K⁺-stimulated respiration.