芹菜素对自发性高血压大鼠的降压作用及对肾脏血管紧张素转化酶2表达的影响

Effects of apigenin on the expression of anglotensin-converting enzyme 2 in kidney in spontaneously hypertensive rats

目的探讨自发性高血压大鼠(SHR)肾脏血管紧张素转换酶2(ACE2)的表达,了解芹菜素对大鼠肾脏ACE2mRNA表达的影响,观察芹菜素的降压效果。方法 60只雄性SHR大鼠随机分为6组,每组10只:正常对照组、卡托普利阳性对照组以及0.007、0.026、0.104和0.417g/kg芹菜素剂量组。4周后,用荧光实时定量PCR法检测肾脏ACE2mRNA表达,免疫组化法检测肾脏ACE2表达。结果自灌胃第3周开始,卡托普利阳性对照组、0.026、0.104、0.417g/kg芹菜素剂量组的血压均显著低于对照组(P<0.05)。各剂量组大鼠心率、体重与对照组比较差异均无显著性(P>0.05)。给予芹菜素4周后,阳性对照和芹菜素高剂量组ACE2mRNA表达量明显升高(P<0.05)。免疫组化所见ACE2表达情况与mRNA表达水平基本类似。结论芹菜素降低SHR大鼠血压与增强ACE2表达有关。

Objective To determine the expressions of angiotensin-converting enzyme 2（ACE2） in spontaneously hypertensive rats and the effect of apigenin Methods Sixty male SHR rats aged 12 weeks were randomly divided into 6 groups based on body weight and blood pressure.The rats in a normal control group and 4 experimental groups were given 0,0.007,0.026,0.104 and 0.417g /kg of apigenin respectively,and the rats in positive control group were given 12mL /kg captopril.Systolic blood pressure（SBP） and heart rate were measured once a week;body weight was measured twice a week.At the end of the experiment,the expression of ACE2 mRNA was determined by real time PCR and the distribution and expression of ACE2 in kidney was determined by immunohistochemistry.SBP was measured by tail-cuff method.Results The transcription level of ACE2 mRNA in captopril positive control group and 0.417g /kg bw apigenin group was significantly higher than the control group（P 0.05）.The immunohistochemistry results were consistent with the gene expression results.Conclusion The effect of apigenin on lowering blood pressure was related to up-regulating the expression of ACE2 in kidney.However,further study is still needed for the possible mechanisms.