Influence of Samarium on Learning and Memory Function of Rats

Sixty-four Spraque-Dawley (SD) big rats with weaning weight of (195 ± 15) g were randomly divided into 4 groups with 8 males and 8 females each group. One group drunk with de-ionized water served as control and was also used for analysis of the background. The other three groups rats were raised by de-ionized water containing low, middle and high concentrations of Sm for four months, then learning and memory tests were carried out in Y-electric maze. Compared with the control rats, the learning and memory of rats in low and middle groups shows a deterioration trend, exhibiting the function degradation of ratsʹ brain. It may results from the rare earth elements through blood-brain barrier affecting the normal physiological functions of ratsʹ brain. In addition, the activity of superoxide dismutase (SOD) in ratsʹ brain decreases, while the content of malondialdehyde (MDA) concentration increases. The decreased SOD activity and the increased MDA mean the degeneration the ability of anti-oxidation in ratsʹ brain, which are accordance with the degradation of learning and memory function of rats in low and middle Sm groups.