“…Acute hippocampal slices were prepared from 4-to 8-week-old male mice as described previously (Huang et al, 2015;Weng et al, 2016;Wang et al, 2017;Yun et al, 2018;Li et al, 2019) with slight modifications to ensure the connectivity of the hippocampal formation with the entorhinal cortex in vitro according to Xiong et al (2017). Briefly, after anesthesia with isoflurane, the brains were isolated and immersed in pre-carbogenated (95% O 2 /5% CO 2 ) ice-cold slicing salt buffer solution (composition in mM: 92 NaCl, 2.5 KCl, 0.5 CaCl 2 •2H 2 O, 10 MgSO 4 , 1.25 NaH 2 PO 4 , 25 glucose, 30 NaHCO 3 , 3 sodium pyruvate, 20 HEPES, titrated to pH 7.4; Pan et al, 2015).…”