Experimental Study On Estrogen Receptor Expression Levels In Different Brain Regions Of Model Rats With Premenstrual Syndrome Liver-qi Depression

Objectives:Our aims of this study are to introduce model rats with Premenstrual Syndrome liver-qi depression, research evaluation method of the model rats; explore expression levels of estrogen receptor in different brain regions; seek for parts of the mechanisms of Premenstrual Syndrome liver-qi depression; and study the effect on Jingqianshu granule acting on the liver-qi depression.Methods : Model rats with PMS liver-qi depression were introduced by bondaging the limbs and using the method of resident-intruder respectively, and some of them were treated with Jingqianshu granule. In the process, we observed the vagina cell shape to make sure the estrum of rats: receptive phases and non-receptive phases, and then estimated model rats by open-field test and tailing suspension test. After introducing model, we killed the rats by decapitation and dissected frontal lobe cortex, hippocampus, hypothalamus and limbic lobe from the brains. Total proteins were extracted from these brain tissues. After that, expression levels of estrogen receptorα&β(ERα, ERβ) were determined in the encephalic regions with western blot method.Results : Compared with the blank group, the body weight of the resident-intruder group (resident group) and the resident-intruder medication administration group (resident-medication administration group) increased significantly (P<0.05,P<0.01). In the tailing suspension test, it showed that in receptive phases, compared with the blank group, the scores of the bondage group increased significantly(P<0.01); While compared with two model groups, the scores of two model- medication administration groups decreased significantly(P<0.01). In non-receptive phases, compared with the blank group, the crossing score, the rearing score and the total score of the bondage group and the resident group in open-field decreased significantly, but scores of tailing suspension test increased significantly(P<0.01); Compared with two model groups, the rearing score and the total score of two model- medication administration groups in open-field increased significantly, but the scores of tailing suspension test decreased significantly(P<0.01). According to the results of western blot , it showed that compared with the blank group , the ERαexpression levels of frontal lobe cortex, hippocampus, hypothalamus and limbic lobe of the bondage group increased significantly(P<0.01); the ERαexpression levels of hippocampus and hypothalamus of the resident group increased significantly(P<0.01), that of frontal lobe cdortex increased, too(P<0.05); however, there was insignificant deviation in every index of the bondage group and resident group. Compared with the model groups, the ERαexpression levels of the medication administration groups decreased with different degrees. Compared with the blank group, the ERβexpression levels of hippocampus, hypothalamus and limbic lobe of the bondage group increased significantly(P<0.01); the ERβexpression levels of frontal lobe cortex and hippocampus of the resident group increased significantly(P<0.01), those of hypothalamus and limbic lobe increased, too(P<0.05); however, there was insignificant deviation in every index of the bondage group and resident group. Compared with the model groups, the ERβexpression levels of the medication administration groups decreased with different degrees.Conclusions:The model rats with PMS liver-qi depression can be introduced by the method of resident-intruder, the model rats can be estimated by open-field experiment, but the tailing suspension test is not fit to estimate the model rats. There is a intimate relationship between the expressions of the ERαand ERβin different brain regions and the PMS liver-qi depression. The syndrome can be cured by the Jingqianshu granule. The changes of the expression levels of ERαand ERβin frontal lobe cortex, hippocampus, hypothalamus and limbic lobe may be one of the reasons that can cause PMS liver-qi depression.