先天性心脏病并肺动脉高压患儿血浆一氧化氮和硫化氢的变化

目的研究先天性心脏病(CHD)并肺动脉高压(PH)患者血浆一氧化氮(NO)和硫化氢(H2S)的变化及其与PH相关性,探论PH的形成机制,为临床有效治疗PH提供新的思路和理论依据。方法对全部研究对象行彩色超声心动图检查,明确CHD类型并测定肺动脉收缩压。按彩色超声心动图结果分为4组。正常儿童25例,CHD 75例,其中无PH 25例,轻度PH 25例,中、重度肺PH 25例。取CHD组术前静脉血4 mL,迅速分离血浆,采用分光光度法测定血浆NO水平,采用敏感硫电极法测定H2S水平。结果CHD患儿血浆NO水平明显高于对照组,但血浆NO水平增加到一定程度后不再随肺动脉收缩压增加而增加,肺动脉收缩压与血浆NO水平无相关性。CHD并中重度PH组血浆H2S水平明显低于CHD并轻度CHD组,CHD并轻度PH组血浆H2S水平明显低于对照组,肺动脉收缩压与血浆H2S水平呈负相关。结论CHD致PH形成时NO水平升高,代偿性内源性NO上调可能对缓解PH起一定作用。CHD致PH形成时H2S明显降低,内源性H2S下调可能在PH形成中起重要的作用。

Changes of Endogenous Nitric Oxide and Hydrogen Sulfide in Plasma of Children with Congenital Heart Disease Complicated with Pulmonary Hypertension

Objective To investigate the changes of nitric oxide(NO) and hydrogen sulfide(H_2S) levels in the plasma in order to explore the role of NO and H_2S in the development of pulmonary hypertension(PH) secondary to congenital heart disease(CHD) and to provide scientific evidence for the decision of treating pulmonary hypertension.Methods There were 75 patients with CHD and 25 normal children as group A,the congenital heart disease children(n=25) without PH as B_1 group,congenital heart disease children with mild pulmonary hypertension(n=25) as B_2 group,congenital heart disease children with moderate-serious pulmonary hypertension(n=25) as B_3 group.The plasma concentrations of NO and H_2S and pulmonary artery pressure(PAP) of each child were measured.Meanwhile,the relationship between NO and H_2S level and PAP was analyzed.Results The plasma level of NO in the group of CHD significantly increased compared with group A,but the level of NO reached maximum and did not correlate with the severity of PH.No correlation existed between plasma NO concentration and PAP.The plasma levels of H_2S in the group of CHD significantly decreased compared with group A.Among these groups,the plasma level of H_2S in B_3 group was lower than that of B_2 group;the plasma level of H_2S in B_2 group was lower than that of B_1 group and a negative correlation existed between plasma H_2S concentration and PAP(r=-0.82 P<0.01).Conclusions Endogenous NO was up-regulated during the development of PH secondary to CHD;it might play a limited role in the development of PH.Meanwhile,endogenous H_2S was down-regulated during the development of PH secondary to CHD,and it might play an important role in the development of PH secondary to CHD.