【作者】 刘立伟；

【导师】 李一石；

【作者基本信息】 中国协和医科大学 ， 内科学， 2010， 博士

【摘要】 研究背景1.美托洛尔在心血管病领域应用广泛,但药物疗效和不良反应存在个体差异,部分患者应用后出现血脂升高。遗传背景是导致个体差异和不良反应的重要原因。以往的研究主要集中在p肾上腺素受体基因多态性上,虽然有阳性,发现但是不能解释所有的差异。2.人体的α和β肾上腺素受体之间存在着密切的联系。α受体可能影响β受体和阻滞剂的相互作用,肾素-血管紧张素系统是β受体阻滞剂发挥降压作用的途径之一,血管的舒缩状态受血管平滑肌细胞和内皮细胞的调节,上述系统中的基因多态性对pβ体阻滞剂疗效的影响少有研究。3.甘油三酯代谢(triglyceride,TG)过程中关键酶的活性高低影响TG的浓度,酶活性大小的改变和相关的基因多态性有关,目前已有的研究尚未明确相关酶的基因多态性和美托洛尔升高TG之间的关系。4.美托洛尔主要由细胞色素酶(cytochrome,CYP)2D6代谢,在中国人中*10多态性是影响酶活性的主要因素,CYP2D6*10和美托洛尔的降血压、心率和升高血脂相关性的研究不多。研究目的1.研究原发性高血压患者服用美托洛尔8周后,血压心率变化与α肾上腺素受体、肾素-血管紧张素系统中相关蛋白基因多态性的关系。2.患者血脂变化和代谢关键酶多态性的关系。3.CYP2D6*10多态性对美托洛尔的降压降心率和血脂升高的影响。研究方法1.临床研究选择2006年5月到2007年3月在阜外心血管病医院门诊就诊的轻至中度原发性高血压患者,服用美托洛尔缓释片95／100mg/天,共8周。评价治疗前后血压、心率、24小时血压监测结果、24小时动态心电图检查结果以及实验室指标(包括血糖、甘油三酯、总胆固醇、高密度脂蛋白、低密度脂蛋白、电解质和肝肾功能等)的变化。2.基因多态性相关研究采用聚合酶链-限制性片段长度多态性分析法(polymerase chain reaction-restriction fragment length polymorphism, PCR-RFLP)、直接测序和TaqMan探针的方法分析基因多态性,包括：血管紧张素转换酶(angiotensin-converting enzyme, ACE) I/D、血管紧张素原(angiotensinogen, AGT) G1566T、血管紧张素Ⅱ1型受体(angiotensin receptors, AGTR1) C961T和A1166C、α1D肾上腺素受体A1903T、内收蛋白(adducin,ADD1)G1566T、内皮型一氧化氮合酶(endothelial nitric oxide synthase, eNOS) Glu298Asp、电压依赖-钙离子敏感型钾离子通道蛋白β1亚基(theβ1-subunit of the large-conductance, Ca2+-dependent K+(BK) channel, KCNMB1)的E65K；脂蛋白酯酶(lipoprotein lipase, LPL) HindⅢ和S447X、低密度脂蛋白受体(low density lipoprotein receptor, LDL)C16370T、载脂蛋白A5(apolipoprotein, APOA5) A-1131G多态性和PLIN (perilipin)蛋白C11482T多态性；CYP2D6*10多态性研究结果1.影响美托洛尔降压降心率作用的基因多态性1.1ACE I/D影响24小时平均心率的下降,携带II基因型的患者心率下降了8.7±8.2次／分,携带FD和DD基因型的患者心率下降了5.5±6.3次／分,P=0.045,在纠正了年龄、体重指数和治疗前的血压后,ACE基因I/D多态性仍然与24小时平均心率下降有关。1.2 eNOS的Glu298Asp影响治疗前后24小时平均收缩压、日间平均收缩压和夜间平均收缩压的下降,GG型患者分别下降了3.3±11.3 mmHg、3.7±11.9 mmHg和3.8±14.9 mmHg,而GT和TT型的患者则分别下降了8.4±8.7 mmHg、5.9±6.2 mmHg和9.9±8.6 mmHg,P值分别为O.021、0.045和0.024。1.3没有发现AGT G1566T、AGTR1 C961T和A1166C、a 1D肾上腺素受体A1903T、ADD1 G1566T多态性、KCNMB1的E65K与美托洛尔的降压降心率有关。2.影响美托洛尔血脂升高的基因多态性2.1 PLIN的C11482T影响美托洛尔引起的TG改变,CC型的TG浓度升高了0.23±1.02 mmol/L,CT型升高了0.26±1.07 mmol/L,TT型升高了1.40±3.21mmol/L,P值是O.045；此外还发现该基因多态性影响治疗前后诊室心率的变化,CC型下降了7.12±9.28次／分,C／T下降了6.8±8.6次／分,TT型下降了-4.0±8.6次／分；P值是0.046。2.2没有发现LPL的HindⅢ和S447X等位点与TG升高存在关联。3. CYP2D6*10多态性有影响有影响治疗前后日间舒张压的变化的趋势,CC型携带者下降6.9±6.8mmHg,CT型下降3.9±6.2 mmHg,TT型下降5.6±6.3 mmHg;两两比较显示,CT型和TT型之间有显著差异(P=0.045)。研究结论1.ACE基因I／D多态性和美托洛尔治疗前后24小时平均心率的差值有关,II型下降最明显。2. eNOS的Glu298Asp多态性和美托洛尔治疗前后24小时平均收缩压、日间平均收缩压和夜间平均收缩压的差值有关,携带T等位基因的患者下降最明显。3. PLIN的C11482T多态性与美托洛尔治疗前后TG的差值和诊室心率的差值有关,TT型TG升高最多心率下降最小。4. CYP2D6*10可能和美托洛尔治疗后日间舒张压改变有关。更多还原

【Abstract】 Background1. Genetic factor can influence the variability in metoprolol’s therapeutic result and adverse effect, many studies focused on the effect ofβ-adrenergic receptor, which a small part of the variability could be derived from.2. Besides P-adrenergic receptor, the polymorphisms in angiotensin-converting enzyme (ACE) and a-adrenergic receptor may affect the antihypertensive response to metoprolol, little is known about their relation.3. The level of triglyceride (TG) in plasma is determined by enzyme involved in its metabolism, the relationship between the elevated TG induced by metoprolol and the polymorphisms of those enzyme is unclear.4. Metoprolol is metabolized by CYP2D6, a few of studies investigated the influence of CYP2D6*10 polymorphism on metoprolol’s therapeutic result and adverse effect.ObjectivesThe aim of the present study was to investigate:1 the association of the polymorphism of ACE and a-adrenergic receptor and proteins in endothelial and smell muscle cells and metoprolol’s therapeutic result; and 2 the association of the polymorphism of enzyme involved in TG metabolism and the elevated TG induced by metoprolol; and 3 the influence of CYP2D6*10 polymorphism on metoprolol’s therapeutic result and adverse effect.MethodsNinety-seven patients with essential hypertension, who visited the FUWAI hospital (from May 2006 to March 2007), received metoprolol (95/100mg once daily) as monotherapy for 8 weeks. Twenty-four hour ambulatory blood pressure monitoring and dynamic electrocardiogram were performed before and after treatment, some biochemical index was measured to assess the influence of metoprolol on metabolism during treatment.The following single nucleotide polymorphisms (SNPs) were determined by polymerase chain reaction with restriction fragment length polymorphism or gene sequencing:angiotensin-converting enzyme (ACE) I/D, angiotensinogen (AGT) G1566T, angiotensin receptor I (AGTR1) C961T and A1166C, a 1D adrenergic receptor A1903T, endothelial nitric oxide synthase (eNOS) Glu298Asp, theβ1-subunit of the large-conductance, Ca2+-dependent K+(BK) channel (KCNMB1) E65K, Lipoprotein lipase (LPL) HindⅢand S447X, Low density lipoprotein receptor (LDL) C16370T, apolipoprotein (APOA5) A-1131G, PLIN C114829T, CYP2D6 C188T.Results1. Association of gene polymorphisms with cardiovascular to metoprolol1.1 ACE gene I/D had an effect on difference in 24-hour average heart rate during the treatment, patients with ACE geneⅡpolymorphism showed greater reduction in 24-hour average HR than those with ID or DD polymorphisms (8.7±8.2 beats/min vs 5.5±6.3 beats/min,P= 0.045).1.2 eNOS Glu298Asp influenced the difference in 24-hour average systolic blood press (SBP) and daytime SBP and nocturnal SBP, in patients with GG genotype the fall was 3.3±11.3 mmHg,3.7±11.9 mmHg and 3.8±14.9 mmHg, while in GT and TT genotypes the fall was 8.4±8.7 mmHg,5.9±6.2 mmHg and 9.9±8.6 mmHg (P value was 0.021,0.045 and 0.024).1.3 The other polymorphisms had no association with the changes in BP and heart rate.2. Association of gene polymorphisms with the elevated TG induced by metoprolol1.1 PLIN C1229T influenced the difference in TG during the treatment, patients with TT genotype had the greatest increase in TG than those with CT or CC genotype (1.40±3.21 mmol/L,0.26±1.07 mmol/L and 0.23±1.02 mmol/L, P= 0.045); and changes of heart rate in clinic were influenced by this polymorphism, the difference in TT was-4.0±8.6 beats/min, in CT was 6.8±8.6 beats/min and in CC beats/min was 7.12±9.28 beats/min, P=0.046.1.2 The other polymorphisms had no association with the changes in TG.3. The influence of CYP2D6*10 on TG and cardiovascular to metoprololA tendency had been observed that the difference in daytime diastolic blood pressure (DBP) was classified by this polymorphism, the reduction was 6.9±6.8 mmHg in CC genotype group,3.9±6.2 mmHg in CT genotype group, and 5.6±6.3 mmHg in TT genotype group. Statistical difference was observed between CT and TT genotype group, P=0.045.Conclusions1. ACE gene I/D had an effect on difference in 24-hour average heart rate during the treatment with metoprolol.2. eNOS Glu298Asp (G/T) influenced the difference in 24-hour average systolic blood press (SBP) and daytime SBP and nocturnal SBP.3. PLIN C11482T influenced the difference in TG and heart rate induced by metoprolol.4. CYP2D6*10 maybe a genetic marker for change in daytime DBP induced by metoprolol.更多还原