In the cerebrocortex, anoxia leads to suppression of spontaneous electrical activity (i.e., spike arrest) [11, 12 ], silencing of AMPA and NMDA receptors [13 –16 ], and large GABA releases during anoxia that activate an inhibitory postsynaptic shunt and prevent presynaptic glutamate release [17, 18 ].
Source: wiktionary