Research On The C-type Natriuretic Peptide Mechanism In Hypothalamus Of The Electro-acupuncture Treatment For Anxiety Disorders

Objective:The study was through observing the effect of electroacupuncture on hypothalamus CNP, NPR-B, NPR-B mRNA expression and the HPA axis changes of CUS anxiety model rats, aiming to explore part of the neuro endocrine mechanisms of electroacupuncture treatment for anxiety disorder, supplementing the mechanism acupuncture’s anti-anxiety effect, and providing scientific experimental basis for the clinical use of acupuncture for the prevention and treatment of anxiety disorders.Methods:Picked out the SD rats of clean grade and then divided them into three groups randomly with the number of weight, respectively for the control group, model group and acupuncture group. The last two groups made chronic emotional stress molding for15days. At the same time, the animals of acupuncture group were given treatments for acupuncturing Shenmen(HT7) and Neiguan(PC6) once every other day. Electroacupuncture apparatus set to dilatational wave, voltage1-3v, frequency15-25Hz,15min each time. The treatment would be lasting from the eighth day to the twenty-second day. Behavioral changes were measured by the elevated plus maze test and open-field test, hypothalamus CNP, NPR-B and CRH expression using immunohistochemical method, hypothalamus NPR-B mRNA expression using the in situ hybridization technique and detecting the content of plasma ACTH and CORT by ELISA.Result:1. The behavioral test results:(1) The elevated plus maze test:control group:the open-arms entries was normal, the model groups with significant decrease(P<0.05). Besides, the acupuncture ones could increase the open-arms entries compared with model group(P<0.05). What’s more, compared with the model group, the open-arms time of acupuncture group reduced more, but the open-arms time of acupuncture group was increase.(2) The open-field test:Compared with the control group, the crossing scores of model group was on the decline; Compared with the model group, electroacupuncture could increase the crossing scores of the CUS anxiety model rat, as well as rearing scores.2. The hypothalamus CNP, NPR-B and NPR-B mRNA level:(1) the CNP level: compared with the control group, the CNP mean optical density of model group increased significantly(P<0.01); compared with the model group, the CNP mean optical density of acupuncture group decreased significantly(P<0.01).(2) NPR-B level:Compared with the control group, the mean optical density of NPR-B increased significantly in model group(P<0.01); compared with the model group, the NPR-B value of mean optical density in acupuncture group was significantly lower(P<0.01).(3)NPR-B mRNA level:compared with the control group, the average optical density of NPR-B mRNA in model group decreased; compared with the model group, the mean optical density of NPR-B mRNA in acupuncture group increased.3. HPA axis changes result:(1) the hypothalamus CRH level:compared with the control group, the CRH immune positive reactant of hypothalamus in model group significantly increased, with a higher optical density value(P<0.01); the mean optical density value of CRH in acupuncture group significantly decreased compared with model group(P<0.05).(2) the plasma ACTH level:compared with the control group, the plasma ACTH levels of model group are higher; levels of ACTH in acupuncture group compared with the model group showed a decreasing trend.(3) the plasma CORT content:compared with the control group, the plasma CORT levels of model group increased; Compared with model group, the serum CORT content in acupuncture group significantly reduced(P<0.05).Conclusion:1. Electroacupuncture has a certain anti-anxiety effect.2. The anxiolytic effects of electroacupuncture may be associated with reducing the CNP and NPR-B level of hypothalamus to suppress the hyperactivity of HPA axis in CUS anxiety model rats, and then corrected the neuroendocrine disorders caused by anxiety.