The changes of NMDA receptor 2B subunit expression in hippocampus of the old rats after establishment of spatial memory

Objective To observe the changes of NMDA receptor 2B mRNA expression in hippocampus of the old rats after establishment of spatial memory.Methods The spatial memory was establishment by reinforcing training in the old rats(12 months).Then the animals were killed eight rats every group at the immediate ,3,6,12,24h and 3d after establishment of spatial memory and the two hippocampus were isolated for determination of mRNA of NMDA receptor 2B subunit(NR2B) expression using RT-PCR technique.Results The training groups (including instant ,3h,6h,12h,24h groups) showed significantly higher expressions of NR2B (683.83±78.13,806.00±81.43,848.83±80.84,915.17±84.25,568.53±77.14) than control group and pseudotraining group (398.17±74.76,418.33±70.17)(P<0.05).AT the moment of 12h got the maximum expression.There were not significantly different between 3d group and control and pseudotraining group.Conclusion NR2B maybe participate in the signal transduction during learning and memory processes ,and got the most at 12h then recovered after 3d. Key words: Y-maze; Spatial learning and memory; NMDA; Hippocampus; mRNA