RESUMO
BACKGROUND: Cardiopulmonary bypass(CPB) induces the productions of several inflammatory mediators that may be implicated in postoperative organ dysfunction, a problem to which the pediatric population is particularly prone. The purpose of this study was to determine if gene expressions of proinflammatory cytokines and chemokines were activated in plasma subjected to pediatric patients who underwent CPB for congenital heart diseases. MATERIAL AND METHOD: Blood was taken from the radial artery of eighteen pediatric patients after induction of anesthesia(baseline), immediately after CPB(0 hour), 2 hours, 24 hours, and 48 hours after CPB. The mRNA expressions of interleukin-1alpha (IL-1alpha ), Interleukin-1beta(IL-1beta), Interleukin-6 (IL-6), Interleukin-8(IL-8), Tumor necrosis factor-alpha (TNF-alpha ), Interleukin-15(IL-15), and Interferon-gamma(INF-gamma) were evaluated with semiquantitative reverse transcription-polymerase chain reaction(RT-PCR). IL-6 protein levels were measured in six patients by using enzyme-linked immunosorbent assay(ELISA.) RESULT: Systemic IL-6 mRNA and protein increased from baseline to a peak at 0 hour(239.5 pg/ml; p=0.01 versus baseline) and sustained at 2 hours before declining at 24 hours(82.7 pg/ml; p<0.05 versus 0hour). In IL-8 mRNA, there was a similar pattern but the increase was smaller than that of IL-6. IL-1 and IL-1 mRNA expressions peaked later(2 hours) from baseline, and declined by 48 hours. TNF- levels peaked at 24 hours, and declined by 48hours. There were no significant differences between before and after bypass were seen in IL-15 mRNA production. IFN- levels gradually decreased during the course of time. CONCLUSION: Gene expressions of IL-6, IL-8, IL-1alpha , IL-beta and TNF-alpha were changed significantly in plasma of pediatric patients who underwent CPB for congenital heart disease. IL-15 showed a different proinflammatory. response, and reverse responses were shown in IFN-gamma mRNA expression. These may result in high concentrations of proinflammatory cytokines and chemokines in the blood after CPB, contributing to the tissue injury.