风湿性心脏病心房颤动患者心房肌11β-羟基类固醇脱氢酶Ⅱ表达研究

目的 探讨心房颤动(房颤)患者心房肌组织11β-羟基类固醇脱氢酶Ⅱ(11βHSD2)mRNA和蛋白表达的改变. 方法 入选进行人工心脏瓣膜置换术的风湿性心脏病患者25例,其中窦性心律(窦律)组12例,持续性房颤组13例(房颤时间≥6个月).上述患者均于术前进行经胸超声心动图检查并留取有关资料,于手术时取左、右心房侧壁组织,用实时荧光定量PCR和Western blot分别测定11βHSD2 mRNA及其蛋白在心房肌组织中的表达情况,用免疫组化染色检测11βHSD2在心房肌细胞中的分布. 结果 与窦律组比较,房颤组左房内径显著扩大(P＜0.01);房颤组患者11βHSD2 mRNA表达明显增加(右房:0.86 ±0.14与0.33 ±0.12,左房:0.95 ±0.15与0.37 ±0.10,P均＜0.01);同时房颤组11βHSD2蛋白表达也较窦律组明显增加(右房:1.18±0.64与0.71 ±0.21,P＜0.01;左房:1.36±0.58与0.85 ±0.15,P＜0.05),但左、右心房之间无论是在窦律或房颤时,11βHSD2 mRNA及其蛋白表达差异均无统计学意义(P＞0.05);免疫组化染色证明,11βHSD2主要分布在心房肌细胞胞质中,且在房颤时其染色密度明显增加. 结论 房颤时心房肌组织11βHSD2表达增加,并可能参与和介导了房颤的心房重构过程.

Atrial 11β-hydroxysteroid dehydrogenase type 2 expression in rheumatic heart disease patients with or without atrial fibrillation

Objective To investigate the Mrna and protein expressions of 11β-Hydroxysteroid dehydrogenase type 2(11βHSD2)in patients with atrial fibrillation.Methods Right and left atrial lateral wall tissue samples were obtained during mitral/aortic valve replacement operation from 25 patients with rheumatic heart valve disease(12 in sinus rhythm and 13 in chronic atrial fibrillation).Realtime quantitative PCR and Western blot were used to determine the Mrna and protein expressions of 11βHSD2 in atria specimens.The distribution of 11βHSD2 in human atrial tissue Was analyzed by specific immunohistochemical staining.Echocardiography examination was performed before operation.Results The left atrial diameters were significantly higher in the atrial fibrillation group as compared to sinus rhythm group (P<0.01).Similarly,Mrna expression of 11βHSD2(0.86±0.14 vs 0.33±0.12 in right atria,0.95± 0.15 vs 0.37±0.10 in left atria,all P<0.01)and protein expression of 11βHSD2(1.18±0.64 vs 0.71±0.21 in right atria,P<0.01:and 1.36±0.58 vs 0.85±0.15 in left atria,P<0.05)were also significantly upregulated in atrial fibrillation groups than those in sinus rhythm groups.The mRNA and protein expressions of 11βHSD2 were similar between left atria and right atria both in fibrillation and sinus groups (all P>0.05).The special immunohistochemical staining demonstrated that 11βHSD2 Was abundant in the human atrial myocardium and located mainly in the cytoplasm.Conclusion These findings suggested that upregulated 11βHSD2 might be associated to the development and persistence of atrial fibrillation.