BAX is necessary for neuronal death following exposure to isoflurane during the neonatal period

Abstract

Exposure to volatile anesthetics during the neonatal period results in acute neuronal death in rodent and non-human primate models, potentially leading to lasting cognitive deficits. We used Bax-/- mice to show that neuronal death following neonatal exposure to isoflurane is mediated by the apoptotic pathway, and that GABAergic interneurons are selectively vulnerable. Neonatal Bax-/- mice also showed attenuated microglial activation after exposure to isoflurane, indicating that neuroinflammatory response is secondary to neuronal apoptosis. Isoflurane-induced neuronal apoptosis in neonates appeared to have little effect on seizure threshold or cognitive function later in life. Collectively, these findings define the acute injury mechanism of volatile anesthetics during the neonatal period.