[Effect of electroacupuncture on the expression of corticotropin releasing hormone (CRH) and CRHR 1 mRNA in paraventricular nucleus of hypothalamus in stress-induced anxiety rats]

OBJECTIVE: To investigate the effects of electroacupuncture (EA) on the expression of corticotropin releasing hormone (CRH) and CRHR 1 mRNA in paraventricular nucleus (PVN) of hypothalamus, to explore its mechanism in anti-anxiety. METHODS: Thirty-three male SD rats were randomly divided into control, model and EA groups. Chronic emotional stress anxiety model was established by using chronic unpredictable emotional stress stimulation for 21 days. EA (15/25 Hz, 1-2 mA) was applied to \"Baihui\" (GV 20) and \"Sanyinjiao\" (SP 6) for 15 min/d and 21 days. The expression of CRH and CRHR 1 mRNA in hypothalamic PVN was measured by immunohistochemistry and in situ hybridization techniques separately. RESULTS: Compared with control group, the values of open-arms entries (OE%) and open-arms time (OT%) in model group were decreased significantly (P<0.01). In comparison with model group, OE% and OT% in EA group were increased obviously (P<0.05, P<0.01). Compared with control group, the optical density values of CRH immuno-reaction positive products and CRHR 1 mRNA expressed neurons of hypothalamic PVN in model group were increased obviously (P<0.05, P<0.01); while in comparison with model group, those of CRH and CRHR 1 mRNA in EA group were significantly decreased (P<0.05, P<0.01). CONCLUSION: EA can effectively relieve chronic stress stimulation induced anxiety in the rat, which is closely related to its effect in down regulating both CRH and CRHR 1 mRNA expression in PVN of hypothalamus.