高血压左心室肥厚与心肌肌浆网钙调节蛋白相关性的实验研究

目的 探讨血管紧张素Ⅱ及肌浆网钙调节蛋白在高血压左心室肥厚形成中的作用和机制。方法 以自发性高血压大鼠,培哚普利治疗组和对照组为模型;分别测定左心室心肌血管紧张素Ⅱ含量,肌浆网Ｒｙａｎｏｄｉｎｅ受体密度和Ｋ受体亲和力及钙ＡＴＰ酶活力。结果左心室在肥厚与心肌ＡｎｇⅡ含量,肌浆网钙调节蛋白及钙ＡＴＰ酶活性相关（１）左心室心肌ＡｎｇⅡ含量：ＳＨＲ组「（１６．７±５．２ｐｇ／ｍｇ」比ＷＫＹ组升高「（１２

The sarcoplasmic reticulum Ca2+ handling protein and left ventricular hypertrophy in SHR

OBJECTIVE: To elucidate the role of myocardial angiotensin II and sarcoplasmic reticulum (SR) Ca2+ handling protein (ryanodine receptor and Ca2+ ATPase) in the process of left ventricular hypertrophy. METHODS: The myocardial angiotensin II level, Bmax and Kd value of ryanodine receptor and calcium ATPase activity in SR were determined among 3 groups: spontaneously hypertensive rats (SHR), SHR treated with perindopril and WKY. RESULTS: The blood pressure (BP) of the SHR group, the ratio of left ventricular weight to body weight (LVW/BW) and the myocardial angiotensin II level were higher than those of the WKY group (P < 0.01), Perindopril decreased the BP(P < 0.01) and the myocardial angiotensin II level, and reversed the LVW/BW of the SHR group (P < 0.05). Compared to the WKY group, the Bmax value of cardiac ryanodine receptor in the SHR group was increased (232 +/- 27) fmol.mg-1 vs (173 +/- 18) fmol.mg-1, (P < 0.01), but there was no difference in Kd value (P > 0.05). The SR calcium ATPase activity was also decreased in the SHR group (0.52 +/- 0.11) mumol.g-1.min-1 vs (1.03 +/- 0.22) mumol.g-1.min-1, P < 0.01]. In the SHR perindopril treatment group, the Bmax of ryanodine receptor was decreased (191 +/- 23) fmol.mg-1, P < 0.05]. There was no difference in Kd value. The calcium ATPase activity was increased (0.82 +/- 0.28) mumol.g-1.min-1, P < 0.05)]. CONCLUSION: The left ventricular hypertrophy is closely related to the myocardial angiotensin II and the SR calcium handling protein.