Figure 2.

cGMP increase does not modify APP expression. A, B, A treatment with vardenafil at different concentrations ranging from 1 to 100 μm does not modify APP full-length expression in N2a cells neither after 1 h (A) nor after 5 h (B) exposure. C, A treatment with 100 μm sildenafil or vardenafil does not modify APP full-length expression in hippocampal slices. Top, Immunoblots; bottom, results of the relative densitometric scan. D, The proteolytic activity of BACE-1 on a secretase-specific exogenous substrate is not modified by treatment of N2a cells with 100 μm vardenafil. Data are mean ± SEM.