The effect of 17 - beta - estrogen on the capability of rat's cognition

doi:10.3321/j.issn:1673-8225.2003.10.007

Abstract：Aim On basis of the results of the orient running test and the spatial search test,together of the observation on the dendritic spines of the pyramidal cells in the CA1 zone of hippocampus,to discuss the effect of estrogen on an emasculated female rat.Methods 28 SD rats (4 - month - old,female,200 g) were divided into 2 groups by sign randomly:estrogen treatment group[0.25 mg/(kg@ d), im] and control group.l0 days later,9 rats in each group were tested in Morris Water Maze for their learning memory.The other 5 in each group were stained with Golgi - Cox technology to observe the structure of the dendritic spine.Results (1)After 10 days, the orient running test showed that the escape latency was (14± 4) s in the control group and (9± 3) s in the treatment group in the later 4 intervals, with a significant difference (t=2.981,P< 0.05).Gogli - Cox showed that the dendritic spines in the estrogen group (19.5 ± 2.3) were significantly increased (t=3.805,P< 0.05), contrast to the control group (25± 3).(2) One month later, the escape latency was (36 ± 9) s in the control group and (17 ± 6) s in the treatment group. The estrogen increased 32%± 5% and 42%± 4% of the total swim path located within the platform quadrant of pool in the control group and the treatment group respectively (t=4.682,P< 0.01).The times crossing the platform was 3.1 and 1.6 separately,with a significant difference (t=4.762,P< 0.01).Conclusion The results suggests that estrogen has an effect on the central nervous system and can enhance the learning memory of female rats.