Effects of formyl tetrahydrofolic acid and noradrenaline on the oxygen consumption of rat brain synaptosome‐mitochondrial preparations

Abstract

1 The respiration of a mitochondrial and synaptasome fraction of rat cerebral cortex was measured using an oxygen electrode. 2 Little or no enhancement of oxygen uptake occurred on separately adding formyl tetrahydrofolate or noradrenaline. 3 When these substances were added together a marked increase in respiration was observed. 4 Both phenobarbitone and phenytoin inhibited the respiration of this preparation, but this was reversed on the addition of formyl tetrahydrofolate. 5 The possibility that some antiepileptic drugs may compete with formyl tetrahydrofolate in the brain is considered and structural similarities between folic acid and these drugs are indicated.