肺炎患儿红细胞离子浓度变化及其与CK、CK-MB关系的研究

Correlation of ionic concentration in RBC with CK and CK-MB activities in children with pneumonia

目的 探讨肺炎患儿不同程度缺氧时钙泵、钠泵活性和红细胞离子浓度的变化 ,及其与CK、CK MB的关系。方法 对 6 1例 5岁以下肺炎患儿同步测定血气分析 ,红细胞钙泵 (Ca2 + Mg2 + ) ATP酶和钠泵 (Na+ K+ ) ATP酶活性 ,红细胞内钙 (EryCa2 + )、镁 (EryMg2 + )和血浆钙 (B Ca2 + )、镁 (B Mg2 + )、钠 (B Na+ )、钾 (B K+ )和游离钙 (B iCa2 + )浓度 ,及血清CK、CK MB ;并与 16例健康儿童比较。肺炎组按照动脉血氧分压 (PaO2 )分为轻度、中度和重度缺氧组。结果 (1)随着肺炎患儿缺氧程度加重 ,(Ca2 + Mg2 + ) ATP酶和 (Na+ K+ ) ATP酶活性下降 ,B Na+ 、B Ca2 + 、B iCa2 + 和EryMg2 + 降低 ,B K+和EryCa2 + 升高 ,尤以重度缺氧组为甚。 (2 )重度缺氧组CK MB活性升高和异常率分别升高到 (99±6 8)U/L和 75 % ,与轻、中度缺氧组比较差异有显著性 (P <0 0 5 )。 (3) (Ca2 + Mg2 + ) ATP酶、(Na+ K+ ) ATP酶活性、B Na+ 及B iCa2 + 与CK MB活性呈负相关 (r分别为 - 0 4 4 1、- 0 30 5、 - 0 4 34、- 0 75 3,P均 <0 0 5 )。结论 缺氧所导致离子稳态失调是引起肺炎患儿心肌损伤的一个原因。钙泵和钠泵活性随缺氧程度加重而下降 ,尤其是钙泵。

Objective To study the changes of erythrocyte membrane Ca + pump and Na + pump activities and ionic concentration in pneumonia children with different degrees of hypoxia, and to analyze their relation to the activities of CK and CK MB Methods The blood samples were taken from 61 pneumonia patients and 16 healthy children Patients were younger than 5 years, and had no sign of any cardiac diseases, such as congenital heart disease, cardiomyopathy and anemia, and so on Their blood gas was measured The activities of erythrocytic (Ca 2+ Mg 2+ ) ATPase (Ca + pump) and (Na + K +) ATPase (Na + pump) were measured by the colorimetry The concentrations of intra erythrocytic calcium (EryCa 2+ ) and magnesium (EryMg 2+ ), and plasma calcium (B Ca 2+ ) and magnesium (B Mg 2+ ) were determined with the atomic absorption spectrophotometry In the meanwhile, the concentrations of plasma sodium (B Na +), kalium (B K +) and free calcium (B iCa 2+ ), as well as the activities of the serum creatine kinase (CK) and creatine kinase MB (CK MB) were also detected The blood samples used for the experiments were drawn before application of the cesium antagonists, cesium and digitalis to the patients According to the oxygen pressure in the arterial blood (PaO 2), the patients were divided into three groups, the mild anoxia group (group Ⅰ), moderate anoxia group (group Ⅱ) and serious anoxia group (group Ⅲ) The age and sex were not notably discrepant among the three groups ( P >0 05) Results (1)Accompanying with the aggravation of the hypoxic degree, the activities of (Ca 2+ Mg 2+ ) ATPase and (Na + K +) ATPase respectively declined to (77±8) and (12±6) μmolPi/(gHb·2h) The concentrations of B Na +, B Ca 2+ , B iCa 2+ and EryMg 2+ decreased to (133 8±2 9),(1 68±0 20),(0 95±0 15)and(0 42±0 08)mmol/L,respectively While the concentrations of B K + and EryCa 2+ increased to (5 7±1 2) and (0 52±0 16)mmol/L, respectively These changes were strikingly distinct in groupⅢ( P <0 05) But the concentration of B Mg 2+ did not change ( P >0 05) (2)In group Ⅲ the activity and abnormal rate of CK MB increased to (99±68)U/L and 75%, respectively, which were significantly different from those in group Ⅰand Ⅱ( P <0 05) In addition, of 8 cases in group Ⅲ, 6 showed that the ratio of CK MB/CK was more than 6%, and 4 presented with the electrocardiogram change (3)The activities of CK MB correlated negatively with the activities of (Ca 2+ Mg 2+ ) ATPase, (Na + K +) ATPase and the concentration of B Na + ( r =-0 441, -0 305 and -0 434, respectively, P <0 05), and correlated positively with the concentration of B iCa 2+ ( r =-0 735, P <0 01) Conclusion The disordered ionic steady state caused by the hypoxia may be one of the reasons of myocardial injury in children with pneumonia The activities of the Ca + pump and Na + pump declined with the aggravation of the hypoxia, especially the Ca + pump The correction of the hypoxia in the early stage may block the deterioration of the disease and prevent the activities declining, ionic disorder and myocardiac injury