<p>(a) Timeline and experimental design. All animals received an infusion (i.c.v.) of Aβ<sub>25–35</sub> (2 µg/µl; 10 µL injection volume) or its vehicle (PBS 10 µL injection volume) and daily treated (7 days) with SP (50 µg/ml/Kg, i.p.) or its vehicle (saline solution 0.9%, i.p.). On the 31<sup>st</sup> day after surgery rats were given a daily training session of 4 trials for 3 consecutive days (days 31<sup>st</sup>–33<sup>rd</sup>). On the 34<sup>th</sup> day after surgery the retention of the spatial training was assessed during a 1 min probe trial. On the 35<sup>th</sup> day after surgery rats were given a daily training session of 5 trials for 4 consecutive days (days 35<sup>th</sup>–38<sup>th</sup>). (b) Mean (±S.E.M.) distance traveled to the escape platform on 4 trials of 3 consecutive days of acquisition learning sessions. (c) Time spent (mean ±S.E.M.) during the 1-minute probe trial in the target quadrant and (d) illustrative paths of all animals for the probe test session. (e) Mean (±S.E.M.) distance traveled to the escape platform on 4 trials of 4 consecutive days of the reversal learning sessions (the hidden platform were relocated in a new position each day). * p<0.05 Aβ<sub>25–35</sub>/Sal <i>vs</i> PBS/Sal; # p<0.05 Aβ<sub>25–35</sub>/Sal <i>vs</i> PBS/SP; $ p<0.05 Aβ<sub>25–35</sub>/Sal <i>vs</i> Aβ<sub>25–35</sub>/SP. PBS/Sal, n = 10; PBS/SP, n = 10; Aβ<sub>25–35</sub>/Sal n = 12; Aβ<sub>25–35</sub>/SP, n = 10.</p
