The study on learning and memory ability and specific brain area antioxidant enzyme activities in D-galactose model rats

Objective To explore the relationship between learning and memory ability and antioxidant enzyme (SOD, CAT, GSH-Px)activities in specific brain areas of D-galactose model rats. Methods The aging models were induced by D-galactose in 3-month old rats, and the learning and memory ability of aging model was detected in model MG-2 maze. The activity of SOD, CAT and GSH-Px in brain cortex, cerebellum,hippocampus, striatum and hypothalamus were detected immediately after rats were executed. Results The learning and memory ability of D-ga-lactose aging model was lower than that of control group. The difference of antioxidant enzyme activity among different rat brain areas was significant. The correct response rate of D-galactose aging model was( 58.9 ± 5.4 ) %, which is significantly lower than that of the control group (66.8 ±8.9) %, P ＜ 0.05. The times of response required reaching the standard after 24h of aging model rats was significantly higher than that of the control( Aging group :29.5 ± 12.8, Control group 16.6 ± 6.2; P＜ 0.01 ). Correct response rate after 24h was significantly lower than that of the control ( Aging group :67.3 ± 10.3 , Control group: 79.1 ± 6.9; P＜ 0.01 ). The SOD activity in cortex, hippocampus and striatum( Aging group :66.12 ±5.89,80.46 ± 6.57,87.82 ± 6.87; Control group :57.63 ± 4.21,67.46 ± 6.80,68.37 ± 6.52) significantly reduced ( P ＜ 0.05 and P ＜ 0.01 ).The CAT activity in cortex, hippocampus, striatum and hypothalamus( Aging group :6.45 ± 0.55,5.86 ±0.35,6.93 ± 0.63,8.89 ± 0.38; Control group :5.32 ± 0.56,4.76 ± 0.38,4.37 ± 043,6.11 ± 0.37) significantly reduced ( P ＜ 0.05 and P ＜ 0.01 ). GSH-Px activity was similar in each brain area without significance ( P ＞ 0.05 ). Conclusions The learning and memory ability of aging mode rats decreased. The change of antioxidant enzyme activities in hippocampus, cortex, striatum and hypothalamus is closely related to learning and memory ability. Key words: Aging;  Learning and memory;  SOD;  CAT;  GSH-Px