The immature brain needs GABA to be excited and hyper-excited.

摘要

The perspective article 'Immature brains don't need GABA to get "hyper"-excited', Goaillard (2010) highlights the paper of Shao & Dudek (2009) who suggested that seizures generated in 'immature' CA3 slices by GABA_A receptor blockers do not depend on the excitatory action of GABA, but on other mechanisms including intrinsic parameters, release properties, recurrent synaptic connections, etc. From this work centred on epilepsies, Goaillard challenges whether GABA excites immature neurons at all, as suggested two decades ago and repeatedly confirmed. It is important to stress that Dudek and Shao conducted their study on CA3 neurons recorded from third week animals when the developmental shift of GABA has already occurred thereby mixing two different issues: the developmental sequence and the effects of seizures. Indeed, GABA can excite adult epileptic neurons because of intracellular chloride accumulation (Cohen et al. 2002). Indeed, Goaillard challenges the concept that GABA excites immature neurons (at an earlier age) relying on the study of Rheims et al. (2009) who claimed that the depolarizing action of GABA is an artifact due to energy deprivation in slices where glucose is the sole metabolic source.