Influence of Aβ on LTP and MTT reduction of acute isolated slices.

<p>A) Influence of freshly dissolved Aβ (25-35), oligomeric Aβ (1-40) and fibrillar Aβ (1-40) on LTP of acute hippocampal slices. Oligomeric Aβ (1-40) significantly reduced the LTP, compared to control potentiation. Freshly dissolved Aβ (25-35) and fibrillar Aβ (1-40) did not effect the LTP; * = p≤0.05 ANOVA with repeated measures; The bar indicates the time of Aβ application. Tetanus was applied at time point 0; Analogue traces represent typical recordings of single experiments taken 20 minutes before tetanization (1), and 240 minutes after tetanization (2). B) Aβ treated acute slices did not differ from control slices in their MTT reduction activity. C) Influence of Aβ on MTT reduction activity of <i>ex vivo</i> slices. Injection of freshly dissolved Aβ (25-35) and oligomeric Aβ (1-42) for 3 days did not diminish the MTT reduction of the <i>ex vivo</i> slices, compared to untreated animals and the reverse control protein Aβ (35-25). D) Immunostaining of cross sections against Aβ revealed the presence of oligomeric Aβ (1-42) in the hippocampus.