Figure 13

Ilantide reduces social memory deficits induced by amyloid-β. Ilantide-t (10 mg/kg; n = 12) or vehicle (saline, 1 ml/kg; n = 13) was subcutaneously injected on days postimmunization (dpi) 7, 9, 11, 13, 15, 17 and 19 after intracerebroventricular administration of aggregated Aβ_25–35 (15 μg). The control group consisted of 11 rats. The social recognition test was performed on dpi 20. Social memory was estimated as the recognition ratio (RR). RR_familiar was calculated as T₂/(T₁ + T₂). T₁ and T₂ are the times spent investigating the same juvenile animal during the first and second trials, respectively. RR_new was calculated as T₃/(T₁ + T₃). T₁ and T₃ are the times spent investigating the different juvenile animals during the first and third trials, respectively. An RR value significantly less than the theoretical value of 0.5 obtained by one-sample t-test was taken as an indication of the presence of social memory. **P < 0.01 and ***P < 0.001 by one-sample t-test compared with theoretical value of 0.5. ⁺ P < 0.05 and ⁺⁺⁺ P < 0.001 by one-way analysis of variance followed by the Newman-Keuls post hoc test.