Objective: To observe the effects of acupuncture at "antihypertensive acupoint prescription" on endothelial active factors and related autonomic neurotransmitters in spontaneous hypertension rats, and explore the vascular regulation and central regulation mechanisms of acupuncture for anti-hypertension.
Methods: Thirty SPF grade male spontaneous hypertension rats were randomly divided into a model group (15 rats) and an acupuncture group (15 rats). Besides, 15 Wistar Kyoto rats were collected as a blank control group (normal group). In the acupuncture group, acupuncture was delivered at the "antihypertensive acupoint prescription" (bilateral "Renying" [ST 9], "Quchi" [LI 11], "Zusanli" [ST 36], "Taichong" [LR 3] and "Neiguan" [PC 6]), with needles retained for 30 min, once daily. The duration of intervention was 28 days. Every week, using the the irritation scale, the sign of sympathetic irritation was evaluated dynamically. The arterial blood pressure of the rats tail was determined, using non-invasive blood pressure measurement system. ELISA was adopted to detect the levels of calcitonin gene-related peptide (CGRP), nitric oxide (NO), endothelin-1 (ET-1), neuropeptide Y (NPY) in the serum. DAB chromogenic in situ hybridization (CISH) was provided to detect the mRNA expression of endothelial nitric oxide synthase (eNOS) in the internal carotid artery and the arcuate nucleus (ARC), and that of CGRP in the paraventricular nucleus posterior (PVP) and the ventrolateral medulla (VLM). Liquid chromatography-mass spectrometry (LC-MS) was used to detect the levels of epinephrine (E) and norepinephrine (NE) in the paraventricular nucleus anterior (PVA).
Results: Compared with the normal group, the irritation scores, systolic blood pressure and diastolic blood pressure were increased at each time point in the model group (P<0.05). When compared with the model group, the irritation scores after the intervention for 3 and 4 weeks, and systolic and diastolic blood pressure after intervention for 2, 3 and 4 weeks were reduced in the acupuncture group (P<0.05). In comparison with the normal group, the serum CGRP and NO levels of the rats were decreased (P<0.05), and the serum ET-1 and NPY levels, as well as E and EN levels in PVA were increased (P<0.05) in the model group. The levels of serum CGRP and NO were elevated (P<0.05), and the serum ET-1 and NPY levels, as well as E and EN levels of PVA were reduced (P<0.05) in the acupuncture group when compared with those of the model group. In the model group, the media of internal carotid artery exhibited thickening and remodeling, while the neuron volume in ARC was small. In the acupuncture group, every layer of internal carotid artery was acceptably arranged, and the parvicellular neuron of ARC was moderate in volume. For the in situ hybridization of eNOS mRNA for the rats of each group, the smooth muscle cells were predominantly expressed in each layer of the internal carotid artery, whereas the expression of parvicellular neurons was dominated in ARC. In the model group, the large and small neurosecretory cells were distributed sparsely in the nerves of PVP; in the acupuncture group, the cells of these two species were distributed regularly; and there were few species of glial cell in the VLM of either the model group or the acupuncture group. In each group, for the in situ hybridization of CGRP mRNA, the small neurosecretory cells were expressed predominately in the PVP, while, the expression of glial cell nuclei and the cell cytoplasm was dominated in the VLM. Compared with the normal group, the mRNA expression of eNOS in the internal carotid artery and ARC and that of CGRP mRNA in the PVP and VLM was decreased in the model group (P<0.05). In the acupuncture group, when compared with the model group, the mRNA expression of eNOS in the internal carotid artery and ARC and that of CGRP in the PVP and VLM was increased in the acupuncture group (P<0.05).
Conclusion: Acupuncture at "antihypertensive acupoint prescription" can upregulate the level of vascular relaxing factors, downregulate the level of contracting factors, enhance the response of relaxing factors in targeting blood vessels and regulating the center. The mechanism may be related to the modulation of the sympathetic-adrenergic autonomic neurotransmitters in the paraventricular nucleus in spontaneous hypertension rats.
目的：观察针刺“降压方”对自发性高血压大鼠（SHR）内皮活性因子及相关自主神经递质的影响，探讨针刺降压的血管调节和中枢调控机制。方法：将30只SPF级雄性SHR随机分为模型组（15只）、针刺组（15只），另以15只京都种Wistar大鼠（WKR）为空白对照组（正常组）。针刺组予“降压方”（双侧“人迎”“曲池”“足三里”“太冲”“内关”）针刺，留针30 min，每日1次，共干预28 d。每周采用激惹评分动态评价大鼠交感激惹表征；通过全自动无创血压测量系统检测大鼠尾动脉血压；ELISA法检测血清降钙素基因相关肽（CGRP）、一氧化氮（NO）、内皮素-1（ET-1）、神经肽Y（NPY）含量；DAB显色原位杂交（CISH）检测颈内动脉、弓状核内皮型一氧化氮合酶（eNOS）及室旁核后部、延髓腹外侧CGRP mRNA表达；液相色谱及质谱联用检测室旁核前部肾上腺素（E）、去甲肾上腺素（NE）含量。结果：与正常组比较，模型组大鼠观察期间各时间点激惹评分及收缩压、舒张压升高（P<0.05）；与模型组比较，针刺组大鼠干预第3、4周后激惹评分及干预第2、3、4周后收缩压、舒张压降低（P<0.05）。与正常组比较，模型组大鼠血清CGRP、NO含量降低（P<0.05），血清ET-1、NPY含量及室旁核前部E、NE含量升高（P<0.05）；与模型组比较，针刺组大鼠血清CGRP、NO含量升高（P<0.05），血清ET-1、NPY含量及室旁核前部E、NE含量降低（P<0.05）。模型组大鼠颈内动脉中膜增厚且有重构表现，弓状核神经元体积较小；针刺组大鼠颈内动脉各层排布尚可，弓状核小细胞神经元适中。各组大鼠eNOS mRNA在颈内动脉主要表达于各层中平滑肌细胞，而在弓状核主要表达于小细胞神经元。模型组大鼠室旁核后部神经分泌大细胞及小细胞分布较为稀疏，针刺组大鼠两类细胞排布尚可；模型组、针刺组大鼠延髓腹外侧区胶质细胞种类相对较少。各组大鼠CGRP mRNA在室旁核后部主要表达于神经分泌小细胞，而在延髓腹外侧主要表达于胶质细胞核及细胞质。与正常组比较，模型组大鼠颈内动脉及弓状核eNOS mRNA、室旁核后部及延髓腹外侧CGRP mRNA表达降低（P<0.05）；与模型组比较，针刺组大鼠颈内动脉及弓状核eNOS mRNA、室旁核后部及延髓腹外侧CGRP mRNA表达增加（P<0.05）。结论：针刺“降压方”可上调血管舒张因子水平，下调血管收缩因子水平，同时增强血管舒缩因子靶向血管及调控中枢的响应，其机制可能与调节SHR室旁核交感肾上腺素能自主神经递质有关。.
Keywords: acupuncture; antihypertensive acupoint prescription; neurotransmitters; spontaneous hypertension; vascular endothelial active substances.