[Effect of Acupuncture on Histology of Thymus and Expressions of ANP and NPR-A in Anxiety Rats].

OBJECTIVE: To explore possible mechanism of electroacupuncture (EA) for regulating immune function in anxiety disorder (AD) rats by observing the effect of acupuncture on the histology of thymus and expressions of atrial natriuretic peptide (ANP) and natriuretic peptide receptor type A (NPR- A) in thymus. METHODS: Totally 34 SD healthy rats were randomly divided into the blank control group (n = 10), the model group (n = 12), the EA group (n = 12). Anxiety model was established in rats of the model group and the EA group by using chronic unpredictable stress (CUS) stimulation. EA (15/25 Hz) at Neiguan (PC6) and Shenmen (HT7) was performed in the EA group, with 15-min needle retaining, once every other day, 15 days in total. Needle was fixed at same acupoints for 15 min without electric stimulus in the other two groups. Anxiety-like behavior was measured by elevated plus-maze (EPM) test. Pathological changes of thymus tissue were observed by optical microscope. Expressions of ANP and NPR-A in thymus were measured by immunohistochemical assay. RESULTS: The thymus tissue in the model group was severely atrophied, with unclear structure of thymic lobules, unclear margin of thymic medulla, loosely arranged lymphocytes ,and obviously enlarged volume of thymic corpuscle. The thymus tissue in the EA group was mildly atrophied, with existent structure of thymic lobules, clear margin of thymic medulla, densely arranged lymphocytes in cortical region, and widened medullary area. Com- pared with the blank control group, the percentage of open-arms entries (OE%) in the total QE times ob- viously decreased in the model group (P < 0.05), ANP expression obviously increased (P < 0.05), and NPR-A expression obviously decreased (P < 0.01). Compared with the model group, OE% was obviously elevated (P < 0.05), ANP expression obviously decreased (P < 0.05), and NPR-A expression obviously increased (P < 0.01) in the EA group. CONCLUSION: EA not only could reduce anxiety of rats, but also could improve chronic stress induced thymus injury through intervening synthesis and secretion of ANP, as well as the expression of NPR-A (a specific receptor of ANP).

[Effects of Acupuncture Intervention on Levels of T Lymphocyte Subsets in Plasma and Thymus in Stress-induced Anxiety Rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) intervention on the levels of CD 4+ and CD 8+ lymphocytes in the plasma and thymus in anxiety disorder rats, so as to explore its mechanism underlying favorable regulation of immune function. METHODS: Thirty-four SD rats were randomly divided into control (n = 10) , model (n = 12) and EA (n = 12) groups. The anxiety model was established by using chronic unpredictable emotional stress stimulation (fasting, water-deprivation, shaking, tail-clamping, forced warm- and cool-water swimming, electrical shock stimulation, etc.) for 15 days. EA (15 Hz/ 25 Hz) was applied to "Neiguan" (PC 6) and "Shenmen" (HT 7) for 15 min, once every other day for 15 days. The anxiety-like behavior was measured by elevated plus maze test. Anxiety reduction in the plus-maze is indicated by an increase in the proportion of time spent in the open arms (time in open arms/total time in open or closed arms) , and an increase in the proportion of entries into the open arms (entries into open arms/total entries into open or closed arms). While the contents and expression of CD 4+ and CD 8+ in the plasma and thymus tissues were measured by ELISA and immunohistochemistry, respectively. RESULTS: The values of proportions of open-arm entries (OE%) and the content of plasma CD 4+ lymphocytes were obviously lower in the model group than in the control group (P < 0.05), and were significantly higher in the EA group than in the model group (P < 0.05). Whereas, the content of plasma CD 8+ lymphocytes was obviously higher in the model group than in the control group (P < 0.05) and markedly down-regulated in the EA group after the treatment (P < 0.05). The ratio of CD 4+/CD 8+ was decreased in the model group in comparison with the control group (P = 0.054), and was significantly up-regulated in the EA group after EA stimulation (P < 0.01). Compared with the control group, the expression levels (optical density, OD values) of CD 4+ and CD 8+ lymphocytes in the thymus tissue were obviously decreased in the model group (P < 0.01). After EA, the expression levels of thymus CD 4+ and CD 8+ were remarkably up-regulated in the EA group (P < 0.05). No significant changes were found in proportion of open-arm time (OT%, P > 0.05). CONCLUSION: EA can effectively relieve anxiety disorder in anxiety rats, which may be related to its effects in up-regulating plasma CD 4+ , thymus CD 4+ and CD 8' levels as well as CD 4+/CD 8+ ratio, and down-regulating plasma CD 8+ content.

[Impacts of acupuncture at Hegu (LI 4) on facial EMG in rhesus monkeys under the physiological state].

OBJECTIVE: To observe the specificity relationship between acupuncture at "Hegu" (LI 4) and the facial muscular movement in rhesus monkeys under the physiological state by using neuromuscular electrical measurement technique. METHODS: Eighteen rhesus monkeys were randomized into a Hegu group, a Houxi group and a Waiguan group, 6 monkeys in each one. Under the physiological state, EMG was detected on the frontal muscle, zygomatic muscle and orbicular muscle before and after acupuncture at different acupoints. The impacts of acupuncture on the facial EMG were studied and compared among different acupoints. RESULTS: With acupuncture at "Hegu" (LI 4), the latency was reduced (P < 0.01) and the peak value and area were increased (P < 0.05, P < 0.01) in the frontal EMG; the area and the peak value were increased (P < 0.01, P < 0.05) and latency was reduced (P < 0.05) in the zygomatic EMG; the frequency was increased (P < 0.01) and the latency was reduced (P < 0.05) in the orbicular EMG. Before and after acupuncture at "Hegu" (LI 4), the change rates of EMG frequency, peak value, area and latency on the frontal, zygomatic and orbicular muscles were higher than those at "Houxi" (SI 3) and "Waiguan" (TE 5) (P < 0.05, P < 0.01) separately. CONCLUSION: The relative specificity presents between Hegu (LI 4) and facial muscular movement.

[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.