Figure 1

Zn²⁺ supplementation prevents the development of hippocampus-dependent memory deficits in 3xTg-AD mice. Male 3xTg-AD mice were treated with either water containing 30 p.p.m. of ZnSO₄ (n=9) or tap water (n=11) for 11–13 months and tested for the spatial memory version of the MWM. (a and b) Mice were given a memory probe trial wherein, the platform was removed 1.5 and 24 h after the last training trial. Compared with untreated 3xTg-AD mice, Zn²⁺-fed 3xTg-AD mice do not show any significant difference in their MWM performance at 1.5 h. (a) When tested at 24 h, mice exhibit a marked decrease in the time (latency) they employed to reach the point where the platform used to be. (b) Zn²⁺-treated 3xTg-AD mice make also more platform crosses, even though such parameter does not reach statistical significance. (c) Zn²⁺ treatment does not affect the performance of the cortex-dependent novel object recognition test as treated and untreated 3xTg-AD mice show no differences in their ability to remember an object to which they were exposed 24 h before. Error bars indicate mean values±S.E.M.; ^*P<0.05