Figure 4.

β1 integrins contribute to the stabilization of object location memory. A, Object location paradigm for studying long-term memory. Panel shows the open field apparatus with two open circles indicating the placement of identical objects; the location of one object is changed on day 2. B, Bar graphs show the discrimination indices of mice treated with neutralizing antisera to β1-integrin (gray bars) expressed as a percentage of measures from paired IgG-treated controls (con; white bars); there were 8–10 mice in each group. As shown, anti-β1 infusion initiated 5 and 20 min after training reduced the time spent with the novel-location object on day 2, whereas anti-β1 infused 60 min after training had no effect (**p < 0.01; ***p < 0.0001 vs same time point IgG con, one-tailed t test). C, Immunostaining for rabbit IgG shows the spread of the anti-β1 in hippocampus for one case killed 40 min after infusion (using techniques used in behavioral studies); the antisera had clearly diffused throughout rostral hippocampus at this time point (scale bar, 0.5 mm).