Fig. 7

cGMP elevation ameliorates oTau-induced memory impairment. a The PDE5 inhibitor 7a (3 mg/kg, i.p.) or the PKG activator 8-pCPT-cGMP (40 μg/Kg, i.p.) protected against the oTau (22.95 μg/ml) induced impairment of RAWM performance). ANOVA for repeated measures among all (day 2): F_(5,83) = 17.973, p < 0.0001. One-way ANOVA for block 10: F_(5,83) = 9.016, p < 0.0001; Bonferroni’s p < 0.0001 oTau vs. vehicle or oTau+ 8-pCPT-cGMP, p = 0.003 vs. oTau+7a. 7a or 8-pCPT-cGMP alone do not modify memory (Bonferroni’s p = 1 compared to vehicle, block 10). Vehicle: n = 15, 8 males, 7 females, oTau: n = 17, 9 males. Eight females, oTau+7a: n = 16, 8 males, 8 females, oTau+ 8-pCPT-cGMP: n = 14, 7 males, 7 females, 7a: n = 14, 7 males, 7 females, 8-pCPT-cGMP: n = 13, 6 males, 7 females. b 7a (3 mg/kg) or 8-pCPT-cGMP (40 μg/Kg) protected against the oTau-(22.95 μg/ml) induced impairment of contextual memory, without modifying memory per se [24 h: ANOVA F_(5,83) = 2.699, p = 0.026; Bonferroni: vehicle vs. oTau: p = 0.036; vehicle vs. oTau+7a or oTau+ 8-pCPT-cGMP or 7a or 8-pCPT-cGMP: p = 1]. No differences were detected during baseline assessment (ANOVA among all: F_(5,83) = 0.978, p = 0.436). Vehicle: n = 16, 8 males, 8 females, oTau: n = 14, 7 males, 7 females, oTau+7a: n = 17, 9 males, 8 females, oTau+ 8-pCPT-cGMP: n = 14, 7 males, 7 females, 7a: n = 15, 8 males, 7 females, 8-pCPT-cGMP: n = 13, 6 males, 7 females. c Freezing responses before (Pre) and after (Post) the auditory cue were the same among the six groups shown in B in the cued conditioning test. ANOVA: Pre-cued: F_(5,83) = 1.223, p = 0.306; Cued: F_(5,83) = 2.010, p = 0.086