Proteomic response to acupuncture treatment in spontaneously hypertensive rats.

Previous animal and clinical studies have shown that acupuncture is an effective alternative treatment in the management of hypertension, but the mechanism is unclear. This study investigated the proteomic response in the nervous system to treatment at the Taichong (LR3) acupoint in spontaneously hypertensive rats (SHRs). Unanesthetized rats were subject to 5-min daily acupuncture treatment for 7 days. Blood pressure was monitored over 7 days. After euthanasia on the 7(th) day, rat medullas were dissected, homogenized, and subject to 2D gel electrophoresis and MALDI-TOF analysis. The results indicate that blood pressure stabilized after the 5th day of acupuncture, and compared with non-acupoint treatment, Taichong-acupunctured rat's systolic pressure was reduced significantly (P<0.01), though not enough to bring blood pressure down to normal levels. The different treatment groups also showed differential protein expression: the 2D images revealed 571 ± 15 proteins in normal SD rats' medulla, 576 ± 31 proteins in SHR's medulla, 597 ± 44 proteins in medulla of SHR after acupuncturing Taichong, and 616 ± 18 proteins in medulla of SHR after acupuncturing non-acupoint. In the medulla of Taichong group, compared with non-acupoint group, seven proteins were down-regulated: heat shock protein-90, synapsin-1, pyruvate kinase isozyme, NAD-dependent deacetylase sirtuin-2, protein kinase C inhibitor protein 1, ubiquitin hydrolase isozyme L1, and myelin basic protein. Six proteins were up-regulated: glutamate dehydrogenase 1, aldehyde dehydrogenase 2, glutathione S-transferase M5, Rho GDP dissociation inhibitor 1, DJ-1 protein and superoxide dismutase. The altered expression of several proteins by acupuncture has been confirmed by ELISA, Western blot and qRT-PCR assays. The results indicate an increase in antioxidant enzymes in the medulla of the SHRs subject to acupuncture, which may provide partial explanation for the antihypertensive effect of acupuncture. Further studies are warranted to investigate the role of oxidative stress modulation by acupuncture in the treatment of hypertension.

[Effect of moderate acupuncture-stimulation of "Taichong" (LR 3) on blood pressure and plasma endothelin-1 levels in spontaneous hypertension rats].

OBJECTIVE: To observe the effect of different strength of acupuncture stimulation on blood pressure and plasma endothelin (E)-1 in spontaneous hypertension rats (SHR) ,so as to seek a better acupuncture parameter for clinical treatment of hypertension. METHODS: Twenty-eight 9-week-old SHRs were randomized into mild-stimulation group, moderate-stimulation group, strong-stimulation group and model group (n = 7 in each group). Seven normotensive SD rats served as a normal control group. Acupuncture stimulation with mild, moderate and strong stimulation was applied to bilateral "Taichong" (LR 3) for 5 min, once daily for 7 days. Blood pressure (BP) was determined by using a non-invasive BP-6 detection system. Plasma ET-1 was assayed by radioimmunoassay. RESULTS: Compared with the model group, the systolic pressure of the moderate-stimulation group on the 6th and 7th day was decreased significantly after acupuncture of "Taichong" (LR 3) (P<0. 01), being significantly lower than that of the mild- and strong-stimulation groups (P<0. 01). In comparison with the normal control group, plasma ET-1 level in the model group was increased significantly (P<0.01), while compared with the model group, only that in the moderate-stimulation group was down-regulated considerably (P<0. 01). No significant differences were found between the mild-stimulation and model groups, between the strong-stimulation and model groups, and between the mild-stimulation and strong-stimulation groups in plasma ET-1 level (P>0. 05). CONCLUSION: Moderate-stimulation of "Taichong" (LR 3) can lower blood pressure and plasma EA-1 level in spontaneous hypertension rats. The reduced level of plasma ET-1 may be one of its mechanisms underlying improving hypertension.