Aging model was induced by s.c.injection D-galactose.Mice were divided into normal group

model group and two selenoarginine groups(8.35 μg Se/kg·d and 16.78 μg Se/kg·d respectively).The selenoarginine was administrated by i.g.method for 42 days.The Morris water maze(MWM) test was used to observe learning and memory abilities of mice.Biochemistry method was used to determine the activities of acetylcholinesterase(AchE) and the protein contents in the brain tissue and brain index were also measured.Results of Morris water maze test show that

after model mice are treated by selenoarginine

the escape latency for finding the hiding platform is significantly shortened compared with the model mice(P0.01);on the other hand

the total crossing numbers at the previous platform and the mean percentages of swimming distance in total swim patch located in the platform quadrant of pool are increased obviously compared with the model mice(P0.01).The swimming search strategies are mainly taxis or random in two selenoarginine groups mice.Biochemistry method shows that

among the seleno-argnine mice

brain index

protein contents and AchE activities in the brain tissue are significantly increased compared with the model mice(P0.01).Selenoarginine is involved in improvement of learning and memory abilities of D-gal aging mice.The protective mechanism of selenoarginine can be attributed to the elevation of the activity of antioxidase and enhanced antioxidant defenses.