Influence of Food form on Learning and Memory in the Early Stage of Aging in SAMP1 mice

Abstract

The purpose of this study was to review whether a senescence-accelerated mouse, P1 (SAMP1), is an appropriate model for the investigation of the influence of different food forms on learning and memory ability. Mice 5 months old were put into either a pellet (hard-diet) or powder (soft-diet) group. A water maze testing of each group was carried out 4 times a day for 5 consecutive days at 3 (1st trial), 10 (2nd trial), and 20 weeks (3rd trial) after the diet was changed. The body weight and the swimming speed showed no significant difference. Escape latency indicating learning and memory ability was the swimming time from an identical start point to the platform. There were no significant differences at the 1st and 2nd trials. However, significant differences were observed at the 3rd trial.The escape latency in the hard-diet group did not change through 5 consecutive days in the 3rd trial, and was almost equal to that on final days in the 1st and 2nd trial. These data suggest that SAMP1 might be an appropriate model for the investigation of the influence of different food forms from early stage of ageing on learning and memory ability. In addition, long-term ingestion of soft diet may influence the learning and memory ability in SAMP1.