Relationship between the ability of learning and memory and activity of antioxidase in specific brain area of rats

Qingsheng KONG; Xiangyang ZHANG; Aiqin SONG; Xiaolin HAN; Yuqing LIU

ABSTRACT

BACKGROUND:

Learning and memory is a very complex biological phenomenon. Although quite a few researches on the substances participate in learning and memory and the brain areas related with learning and memory,its mechanism is still not completely clarified.

OBJECTIVE:

ro study the difference of antioxidase activity at different brain area in rats with different ability of learning and memory to reveal the relationship between the ability of learning and memory and the activity of antioxidase in specific brain area.

DESIGN:

A randomized controlled trial based on the experimental animals.

SETTING:

Department of Biochemistry in Jining Medical College.MATERIALS The study was conducted in the Laboratory of Biochemistry of Jining Medical College and Suzbeu Medical College between March 2001 and January 2004. Forty 15-month old male Wistar rats with a body mass between 580 g and 650 g were selected.

INTERVENTIONS:

The detection of learning memory ability was carried out in MG-2 trisection radiation maze. Correction response was that the rats escaped to safe area after electric shock. Standard of master was that the rats had 9 out of 10 times continuously of correction. Observatory indicators included times of response required reaching the standard and the correct response rate. Good learning. ability meant 40 or less than 40 times of responses to reach standard; otherwise, poor learning ability was considered. Detection was repeated after 24 hours to observe the memory. Good memory meant 3 times continuously of correct response; otherwise, poor memory was considered. Rats with good learning ability and memory were included into group 1 (n= 10) and the rats with poor learning ability and memory were included into group 2( n = 12). The rest rats were washed out.MAIN OUTCOME

MEASURES:

Activities of superoxide dismutase (SOD), catalase(CAT) and glutathione-peroxidase(GSH-Px) of five brain areas including cerebral cortex, cerebella, striatum, hippocampus and hypothalamus in rats of two groups.

RESULTS:

To compare the rats with poor learning and memory ability with rats with good learning and memory ability SOD activity in cortex, hippocampus and striatum significantly reduced ( t = 3.82, 4. 50, 6. 76, P ＜0.01); CAT activity in cortex, hippocampus, striatum and hypothalamus significantly reduced(t =4.75, 7.06, 10. 88, 17.28, P＜0.001); and GSH-Px activity was similar in each brain area without statistical significance.

CONCLUSION:

Hippocampus, cortex, striatum and hypothalamus all might participate in learning memory process, and the activities of antioxidases in these areas are closely related with learning memory.