Reducing EphB2 synthesis in IL of adult rats does not affect fear extinction. A, Percentage of time that P60 rats spent freezing to the tone during fear conditioning (day 1, 1 habituation tone plus 3 tone–shock pairings) and extinction (day 2, 15 tones). Red arrow indicates the time point of euthanasia. B, EphB2 mRNA expressed by each group (COND group, n = 13; CR group, n = 7; EXT group, n = 9). All values are relative to B-actin and GAPDH. C, EphB2-shRNA (n = 11) and scramble-shRNA (n = 9) plasmid infusions were localized to IL. D, Expression of plasmid GFP after infusion into IL. E, Percentage of time that P60 rats spent freezing to the tone during fear conditioning (day 1, 1 habituation tone plus 3 tone–shock pairings) and five partial extinction sessions (days 4–8, four tones per day). Black arrows indicate the time point of IL infusions. *p < 0.05.