A. The escape latency of rats in each group examined by Morris water maze test.
Escape latency (s)	Sham	HI	HI+S	F value	DF
Day1	68.1±3.5	74.8±2.1	74.1±4.8	356.2	2
Day2	54.8±4.8	70.2±4.7*	67.7±2.4
Day3	35.2±3.0	68.3±5.7*	51.0±4.6**
Day4	25.4±3.6	52.1±4.4*	35.1±3.9**
Day5	19.7±3.4	44.8±3.1*	26.0±4.4**

One-way ANOVA was used to compare the mean difference among the three groups. Tukey’s multiple comparisons test was used for post hoc test. F value correspond to the treatment, the time and the interaction between treatment and time in the one-way ANOVA;

^*p<0.001 between sham group and HI group,

^**p<0.001 between HI group and HI+S group.