Prior research has shown that 3xTg-AD exhibit impaired spatial memory on short-term (1.5-h) and long-term (≥24-h post training) memory probe trials in the MWM (Billings et al., 2005). Our results differ from that work, however, in that only the alcohol-exposed 3xTg-AD mice demonstrated a memory deficit on the probe trial conducted 1-h post acquisition (Fig. 5A). This deficit in performance on the probe trial could be a function of poor performance during acquisition; however, this interpretation does not seem likely since saccharin exposed (control) 3xTg-AD mice showed a similar pattern of performance during acquisition but exhibited normal performance on the memory probe trial. This suggests that the level of performance by both groups of 3xTg-AD mice during acquisition was sufficient to support normal performance on the probe trial. Overall, these data indicate that nondependent alcohol use produced a deficit in hippocampal-dependent spatial memory.
