白蒺藜有效组分对自发性高血压大鼠心肌结缔组织生长因子表达的影响

目的观察白蒺藜有效组分对自发性高血压大鼠心肌结缔组织生长因子（CTGF）表达的影响,探讨白蒺藜有效组分改善心室重构的可能作用机制。方法 32只14周龄雄性自发性高血压大鼠随机分为模型组、卡托普利组、白蒺藜组、联用组,每组8只,同周龄雄性Wistar大鼠8只作为正常对照组。用药组分别给予卡托普利30mg.kg-1.d-1,白蒺藜有效组分15mg.kg-1.d-1,白蒺藜有效组分15mg.kg-1.d-1＋卡托普利30mg.kg-1.d-1,模型组及对照组采用等量0.9%NaCl溶液,连续灌胃8周。采用尾动脉容积法测定血压;分离左心室,透射电镜观察心肌超微结构;RT-PCR法检测心肌转化生长因子β1（TGFβ1）、CTGF mRNA含量变化。结果与Wistar大鼠比较,14周龄SHR大鼠收缩压明显升高（P〈0.01）。8周后,模型组大鼠收缩压明显较14周龄时明显升高（P〈0.05）,通过透射电镜对心肌超微结构观察提示,22周龄SHR出现明显的心肌纤维化;且模型组TGFβ1及CTGF mRNA较正常组表达明显增加（P〈0.05）。与模型组比较,白蒺藜组收缩压明显下降（P〈0.01）,并可明显改善心肌超微结构,显著下调TGFβ1及CTGF mRNA水平（P〈0.05）。卡托普利和白蒺藜联用可明显下调TGFβ1mRNA水平（P〈0.05）。结论自发性高血压大鼠心室肌TGFβ1及CTGF表达明显增加,白蒺藜有效组分可显著抑制TGFβ1及CTGF基因表达水平,从而保护高血压病所致的靶器官损伤。

Effects of tribulus-terrestris-L on expression of connective tissue growth factor in myocardium of spontaneously hypertensive rats

Objective To study the effects of tribulus-terrestris-L on myocardial connective tissue growth factor expression in spontaneously hypertensive rat （SHR）, and discuss the possible mechanisms of tribulus terrestris L in inhibiting myocardial fiberoeis. Methods Thirty-two 14-week-aid male SHRs were randomized into 4 groups （n =8） ： model group receiving normal saline （2 ml/rat.d）, eaptopril group receiving captopril （30 mg/kg.d）, tribulus-terrestris-L group receiving tribulus-terrestris-L （30 mg/kg ~ d） and combination group receiving both captopril （30 mg/kg.d） and tribulus-terrestris-L 15 mg/kg.d）. Fourteen-week-old male WKY rats （n =8） were used as a con- trol. Systolic blood pressure （SBP） was measured. The ultra-structure of left ventricle was observed by electron microscope. Myocardial TGFI31 mRNA and CTGF mRNA were detected by RT-PCR. Results Compared with Wistar rats, systolic blood pressures of SHR at 22 weeks were significantly increased （P 〈0.01）, and systolic blood pressures were also obviously higher at 22 weeks than at 14 weeks （P 〈0.05）. Compared with model group, SBP was significantly decreased in tribulus-terrestris-L group （P 〈0.01 ）, captopril group （P 〈0.01 ） and combination group （P 〈0.01 ）. Myocardial fibrosis changes were observed in SHKs at 22 weeks, and rats in all the groups treated with medicine were obviously improved by electron microscope. Myocardial TGFI31 mRNA levels of SHRs in model group were significantly heightened （P 〈0.01 ）. Captopril down-regulated the levels of myocardial TGFI31 mRNA significantly （P 〈0.05 ）, tribulus terrestris L and combined with captopril and significantly down-regulated TGFI81 rrffLNA level （P 〈0.05 ）. CTGF mRNA levels in myocardium of SHRs in model group were obviously ascended compared with normal group. Captopril significantly down-regulated the myocardial CTGF mRNA expression （P 〈0.05）. Tribulus terrestris L could down-regulate the levels of CTGF mRNA expression （P 〈0.05 ）. Conclu- sion Myocardial TGF31 and CTGF mRNA levels of SHRs in model group are significantly heightened, while tribulusqerrestris-L ribulus terrestris L can block the expres- sion of the two cytokine, and inhibit the remodeling of myocardium caused by hypertension.