The effect of metabolic inhibitors on respiration and glycolysis in electrically stimulated cerebral-cortex slices

Recent studies on the metabolism of brain-cortex slices in vitro have shown that under suitable condi- tions some of the changes associated with the passage of electrical impulses, namely increased oxygen uptake, increased glycolysis and increase of inorganic phosphate levels, together with a decreased concentration of creatine phosphate, parallel those which can be reproduced in vivo by similar treat- ment (cf. Mcllwain, 1951a; 1952). Using this technique it has been found that certain drugs of therapeutic value repress the stimulated oxygen uptake and glycolysis of separated slices of cerebral cortex, although they do not have a similar effect on unstimulated metabolism (see Anguiano & McIlwain 1951; McIlwain, 1953a). Measurement of the effect of these drugs has been made in terms of metabolic events such as oxygen uptake and lactic acid pro- duction. From such measurements it has not always been easy to decide whether the drug affects primarily a metabolic process or one more closely associated with excitation (see McIlwain, 1953b).