儿童心衰患者血清抗β_3肾上腺素受体自身抗体对乳鼠心肌细胞跳动频率的影响  

Effects of anti-β_3 adrenoceptor antibody from children with heart failure on the beating rate of cultured neonatal rat cardiomyocytes

作　　者：王瑾[1] 李文孝[2] 闫莉[1] 王晓樑[1] 吕小萍[1] 张睫[1] 刘慧荣[1] 

机构地区：[1]山西医科大学生理学教研室,太原030001 [2]长治市妇幼保健院

出　　处：《山西医科大学学报》2007年第2期106-109,共4页Journal of Shanxi Medical University

基　　金：长治市卫生局基金资助项目(2005012);山西省回国留学人员科研基金资助项目(200526);山西省科学技术厅基金资助项目(2006011106);国家自然科学基金资助项目(30670835)

摘　　要：目的观察儿童心力衰竭患者血清中抗β3肾上腺素受体(β3AR)自身抗体对乳鼠心肌细胞跳动频率的影响。方法①以人β3AR细胞外第二环176-202氨基酸残基序列的合成肽段作为抗原,采用ELISA筛选正常儿童和心衰儿童血清中抗β3AR自身抗体。用亲和纯化法提纯抗β3AR自身抗体阳性血清中的IgG。②设立β3AR激动剂BRL37344、β3AR自身抗体阳性血清IgG、β3AR自身抗体阳性血清IgG+β1AR、β2AR阻断剂Nadolol、β3AR自身抗体阳性血清+非特异性βAR阻断剂Bupranolol、β3AR自身抗体阳性血清+β3AR抗原、阴性对照IgG以及空白对照各组观察该抗体对乳鼠心肌细胞跳动频率的影响。结果①心衰儿童血清中抗β3AR自身抗体的阳性率为30%(15/50),明显高于正常同质儿童的12%(6/50,P<0·05);②该抗体可以使培养的乳鼠心肌细胞跳动频率下降[由(128.0±10.86)次/min下降为(64.7±8.72)次/min,P<0·01];③该作用不能被β1、β2受体阻断剂Nadolol阻断,但可被非特异性β受体阻断剂Bupranolol或β3AR细胞外第二环抗原肽段阻断;④该抗体的负性变时效应在观察时间内(6h)无衰减。结论儿童心衰患者血清中含有较高滴度的抗β3AR自身抗体并具有负性变时效应,且该抗体的负性变时效应具有不脱敏现象。Objective To investigate the effects of anti-β3 adrenoceptor antibody from children with heart failure on the beating rate of cultured neonatal rat cardiomyocytes. Methods （1）The synthetic peptide corresponding to the sequence of the second extracellular loop （176 -202 amino acid residue）of the human β3AR was used as the antigen to screen the anti-β3AR autoantibodies from sera of 50 children with heart failure and 50 healthy subjects by ELISA. （2）BRL37344（selective β3AR agonist） ,the positive sera for anti β3AR autoantibodies, the positive sera for anti-β3AR autoantibodies ± the Nadolol（β1 and β2 antagonist）, the positive sera for anti- β3AR autoantibodies ± Bupranolol（non-selective βAR antagonise）, the positive sera for anti-β3AR autoantibodies ± β3AR specific antigen, negative control and blank control were added to the medium of cultured neonatal rat cardiomyocytes to observe the effects of antibody on the heart beating rate. Results （3）Among the 50 children with heart failure, the anti - β3AR autoantibodies were positire in 15 children（30 % ）, obviously higher than that in healthy children（ 12 %, 6/50, P 〈 0.05）. （3）The autoantibodies （0.1 μmol/ L） could decrease the beating rate of cultured neonatal rat cardiomyocyte [ （64.7± 8.72）counts/min] compared with controls[ （128 ± 10.86）counts/min], P〈0.01. （3）The effect could not be blocked by pretreating myocytes with Nadolol（β3AR and 132AR antagonist） ,but could be blocked by Bupranolol（non-selective βAR antagonist） or β3AR specific antigen. （4）Chronotropic effects of anti-β3AR autoantibodty on the beating neonatal rat cardiomyocytes could persist within 6 hours. Conclusion The positive rate of the anti-β3AR antibodies in the sera of the children with heart failure is obviously higher than that of homogeneous healthy subjects. The autoantibodies can induce β3AR agonist-like negative chronotropic effects which are resistant to short-term desensitization.

关 键 词：儿童 受体 肾上腺素能β3 自身抗体 心力衰竭 充血性 心率 

分 类 号：R541.61[医药卫生—心血管疾病]