体位性心动过速综合征儿童血浆尾加压素Ⅱ和儿茶酚胺抑素的变化及意义

Change and significance in the levels of plasma urotensin Ⅱ and catestatin in children with postural orthostatic tachycardia syndrome

目的:通过检测体位性心动过速综合征(postural orthostatic tachycardia syndrome,POTS)患儿心血管活性肽含量的变化,探索其发病机制。方法:采用临床对照研究的方法,POTS组为于北京大学第一医院儿科门诊就诊的POTS儿童46例(平均12.1±2.8岁),对照组为健康儿童20例(平均11.5±3.6岁),采用酶免疫法测定血浆尾加压素Ⅱ(urotensinⅡ,UII)及儿茶酚胺抑素(catestatin,Cs)浓度,分析POTS组患儿血管活性肽含量的变化及与直立后心率变化的相关性。结果:与对照组相比,POTS组患儿血浆UII水平降低[0.41(0.27,0.85)μg/L vs.0.46(0.35,1.41)μg/L,P<0.05],血浆UII水平与直立10 min后心率的变化次数呈负相关(相关系数-0.363,P<0.05),血浆Cs浓度两组差异无统计学意义[0.48(0.20,1.91)μg/L vs.0.52(0.18,1.60)μg/L,P>0.05]。结论:POTS患儿血浆UII水平降低,提示血管张力调节异常可能是POTS的发病机制之一。

Objective：To explore possible mechanisms by analyzing cardiovascular bioactive peptides levels in children with postural orthostatic tachycardia syndrome（POTS）.Methods：Forty-six children diagnosed as POTS（POTS group,aged 12.1±2.8 years） and 20 healthy children（control group,aged 11.5±3.6 years） were enrolled as controls in this clinical controlled study.Two kinds of cardiovascular bioactive peptides named urotensin Ⅱ（UII） and catestatin（Cs） were measured by using enzyme immunoassay.The comparisons between the two groups were made by independent t test or non-parametric test.Correlation analyses between plasma levels of bioactive peptides and changes in heart rate during standing test or head-up tilt test（HUT） were conducted using bivariate correlations.Results：The plasma UII levels were significantly lower in POTS group as compared with those of controls [0.41（0.27,0.85） μg/L in POTS group vs.0.46（0.35,1.41） μg/L in control group,P〈0.05].The plasma UII level was negatively correlated with the increase in heart rate during standing test or head-up tilt test（correlation coefficient-0.363,P〈0.05）.No difference was found in plasma Cs levels between the two groups [0.48（0.20,1.91） μg/L in POTS group vs.0.48（0.20,1.91） μg/L in control group,P〉0.05].Conclusion：POTS children had low levels of plasma UII,and disturbance of vascular tone regulation might play a role in POTS of children.