RAd-IGF-I prevents LPS-induced nuclear translocation of the NFκB p65 subunit. Astrocyte cultures were treated for 24 h with RAd-IGF-I and for 1 h with LPS, and the level of p65 immunoreactivity in nucleus and cytoplasm was determined. A-D, Representative examples of p65 immunostaining in astrocytes incubated with RAd-TK/GFP (A), RAd-TK/GFP + LPS (B), RAd-IGF-I (C) and RAd-IGF-I + LPS (D), Scale bar, 40 μm. E, Results of densitometric analysis of p65 immunoreactivity expressed as a ratio between immunoreactivity in the cell nucleus and the cell cytoplasm. Data are presented as mean ± SEM and are expressed as percentage of control (uninfected cells treated with vehicle) values. ++,+++ Significant differences (++P < 0.01, +++P < 0.001) between LPS and its vehicle. *, Significant difference (*P < 0.05) versus uninfected + LPS and versus RAd-TK/GFP + LPS values.