Since GABAB receptors are downregulated under excitotoxic/ischemic conditions occurring in cerebral ischemia (Guetg et al., 2010; Maier et al., 2010; Terunuma et al., 2010; Kim et al., 2011; Kantamneni et al., 2014; Zhu et al., 2015; Huang et al., 2017; Hleihil et al., 2021; Balakrishnan et al., 2022; Bhat et al., 2022), we tested the ability of PP2A-Pep to normalize GABAB receptor expression/function and its neuroprotective activity in vitro using glutamate-stressed neuronal cultures and in the MCAO mouse model of cerebral ischemia ex vivo. Here, PTPA is linked to brain ischemia.