Abstract:

Abstract:Objective To observe the effects of estrogen on the behavior and the norepinephrine level in the habenular nucleus of depressive rats,and explore the mechanism of estrogen involved in the process of antidepression.Methods Thirty rats were chosen from forty male Wistar rats,which had the similar scores in open field test.The depression models of rats were established by chronic mild stress.Open field test and forced swimming test were performed to detect the behavioral changes between rats with ovary excision (OVX) and with estradiol-treated ovary excision (OV/ER).High performance liquid chromatography (HPLC) was used to observe the changes of norepinephrine level in habenular nucleus.Results After 21-day chronic mild stress,the open field test showed that the vertical motion and cross motion  in OV/ER group were increased(P<0.05) and the immobile time in OV/ER group was decreased(P<0.05),when compared with those in OVX group.Forced swimming test demonstrated that the climbing time in OV/ER group was higher than that in OVX group (P<0.05);while the immobile time in OV/ER group was obviously lower than that in OVX group (P<0.05).The norepinephrine level　 in the habenular nucleus in OV/ER group was obviously increased compared with OVX group (P<0.05).Conclusion The habenular nucleus is a target of estrogen in central nervous system,which can take part in the antidepressive effect induced by estrogen.

Key words: depression, estradiol, habenular nucleus, norepinephrine