針刺對自發性高血壓大鼠心肌ANP、ACE2表達和Ang（1-7）/AngⅡ 比值的影響

紀智　袁靜云　王紫娟　張躍　梁靖蓉　吳嬌娟　劉清國

[摘要] 目的 通過觀察自發性高血壓大鼠（SHR）心肌組織結構和腎素-血管緊張素-醛固酮系統（RAS）作用因子表達的變化，探究針刺對高血壓心肌肥厚的防護機制。 方法 將10只WKY大鼠作為空白組，將20只SHR按照隨機數字表法分為模型組和針刺組，每組各10只。所有大鼠均為10周齡SPF級雄性大鼠。適應性飼養1周后，針刺組大鼠用毫針于“百會”和雙“太沖”直刺，每天1次，連續干預28 d。模型組和空白組不做針刺干預。于實驗第1、7、14、21、28天針刺前測量血壓值。實驗結束后稱取大鼠全心及左心室重量，并計算心臟重量指數（HWI）和左心室重量指數（LVWI）。應用HE和Masson染色法觀察心肌組織形態，并通過Real-tiem PCR、Western blot、酶聯免疫吸附測定（ELISA）等技術檢測各組大鼠心肌組織中心房鈉尿肽（ANP）、血管緊張素轉換酶2（ACE2）、血管緊張素1-7[Ang（1-7）]和AngⅡ的表達，并計算Ang（1-7）/AngⅡ。 結果 與空白組比較，模型組大鼠收縮壓（SBP）、HWI、LVWI顯著升高（P < 0.01）。與模型組比較，針刺組大鼠SBP、HWI、LVWI值明顯降低（P < 0.05或P < 0.01）。病理切片結果顯示，與空白組比較，模型組大鼠心肌細胞的細胞體積明顯變大，且排列相對紊亂，同時細胞間距變寬，充斥著大量被藍染的纖維。與模型組比較，針刺組大鼠心肌細胞體積更小，細胞間距更窄，細胞間隙藍染的纖維變少。與空白組比較，模型組心肌組織的ACE2的表達水平和Ang（1-7）/AngⅡ顯著降低（P < 0.01），ANP的表達水平升高（P < 0.01）。與模型組比較，針刺組ACE2的表達水平和Ang（1-7）/AngⅡ的比值顯著升高（P < 0.01），ANP的表達水平降低（P < 0.01）。 結論 針刺“百會”“太沖”可通過調節ACE2/Ang（1-7）的表達，有效降低SHR血壓，并減輕其心肌肥厚的程度。

[關鍵詞] 高血壓;針刺;心肌肥厚;血管緊張素轉換酶2;血管緊張素1-7

[中圖分類號] R544.1? ? ? ? ? [文獻標識碼] A? ? ? ? ? [文章編號] 1673-7210（2019）06（b）-0004-05

Effect of acupuncture on the expression of ANP， ACE2 and Ang（1-7）/ AngⅡ ratio in heart tissue of spontaneously hypertensive rats

JI Zhi? ?YUAN Jingyun? ?WANG Zijuan? ?ZHANG Yue? ?LIANG Jingrong? ?WU Jiaojuan? ?LIU Qingguo

School of Acupuncture and Massage， Beijing University of Chinese Medicine， Beijing? ?100029， China

[Abstract] Objective To investigate the protective mechanism of acupuncture on myocardial hypertrophy by observing the changes of myocardial tissue structure and renin angiotension system （RAS） system action factor expression in spontaneously hypertensive rats （SHR）. Methods Ten Wistar Kyoto rats （WKY） were selected as normal control group， 20 SHRs were divided into model group and acupuncture group by random number table method， with 10 rats in each group. All rats were SPF grade male 10-week-old rats. After one week of acclimatization， acupuncture was applied on Taichong （LR3） and Baihui （DU20） of SHRs in acupuncture group once a day for 28 days. The other two groups only received the same grasping and fixation stimulation. Blood pressure was measured before acupuncture on day 1， 7， 14， 21 and 28. At the end of the experiment， the weight of the whole heart and left ventricle of the rats were weighed， and ratio of left ventricle weight to body weight （LVWI）， heart weight index （HWI） were calculated. HE and Masson staining method were applied to observe the myocardial tissue morphology， and Real-time RCR， Western blot， enzyme linked immunosorbent assay （ELISA） were used to detect the expression of atrial natriuretic peptide （ANP）， angiotensin-converting enzyme 2 （ACE2）， angiotensin （1-7） [Ang（1-7）]， AngⅡ and Ang（1-7）/AngⅡ， as well as the underlying mechanisms were investigated. Results Compared with normal control group， the systolic blood pressure （SBP）， HWI and LVWI in the model group were significantly increased （P < 0.01）. Compared with the model group， SBP， HWI and LVWI values in the acupuncture group were significantly decreased （P < 0.05 or P < 0.01）. The pathological results showed that compared with normal control group， the cell volume of rat cardiac muscle cells in the model group was significantly larger， and the arrangement was relatively disordered. Meanwhile， the cell spacing was widened， and there were a lot of blue-stained fibers. Compared with the model group， the cardiac muscle cells in the acupuncture group were smaller in volume， narrower in cell spacing， and fewer blue-stained fibers in the cell space. Compared with normal control group， the expression level of ACE2 and Ang （1-7）/AngⅡ of myocardial tissue in model group significantly decreased （P < 0.01）， the expression level of ANP significantly increased （P < 0.01）. Compared with model group， the expression level of ACE2 and Ang （1-7）/AngⅡ in acupuncture group significantly increased （P < 0.01）， the expression level of ANP significantly decreased （P < 0.01）. Conclusion Acupuncture at LR3 and DU20 could reduce blood pressure and inhibit the development of cardiac hypertrophy， which might be mediated by the regulation of ACE2/Ang（1-7） pathway.

[Key words] Hypertension; Acupuncture; Myocardial hypertrophy; Angiotensin-converting enzyme 2; Angiotensin （1-7）

高血壓病患者的心臟損傷往往開始于病理性心肌肥厚，長時間的壓力負荷往往引起心肌細胞的肥大[1-2]。腎素-血管緊張素-醛固酮系統（renin-angiotensin system，RAS）在調節血壓、維持心肌正常結構功能等方面具有極其重要的作用。血管緊張素轉換酶2（angiotensin-converting enzyme 2，ACE2）和血管緊張素1-7[angiotensin（1-7），Ang（1-7）]是RAS系統中起降壓作用的一條軸線，對心血管系統起到保護作用[3]。研究表明，針刺可降低血壓，改善心肌肥厚，預防其并發癥[4-5]。本研究通過觀察針刺對自發性高血壓大鼠（SHR）血壓和心肌肥厚程度及對ACE2/Ang（1-7）軸表達的影響，探究針刺調控的內在機制，以期為高血壓和心肌肥厚的臨床治療提供新的思路。……