<p><b>a</b>) Example of Western blot obtained from hippocampal cultures exposed to 20 µM Aβ<sub>25–35</sub> (Aβ alone or in the presence of SP (100 nM) and analyzed 48 h later using a polyclonal antibody against Kv1.4 subunit. The same blots were stripped and reprobed with an antibody against β-actin as internal control (lower panels). Quantitative analysis is depicted below the blots and was determined by band densitometry analysis considering the values found in CTR cells as 100. Data represent means (±S.E.M.) obtained from 4 independent experiments run in duplicate. (**p<0.001 versus CTR, #p<0.05 versus Aβ<sub>25–35</sub> treatment). <b>b</b>) Representative immunofluorescence photomicrographs showing Kv1.4 expression in primary hippocampal cultures. Note the increase in immunofluorescence in the Aβ<sub>25–35</sub> neurons, as compared to control neurons, reversed by SP treatment. Images were obtained from three independent experiments. Scale bar: 20 µm.</p