Study on Pulmonary Surfactant of Sudden Death of Infant

Song Jiazhen; Guo Sixia

摘要：Objective To find the pathogenesis of sudden infant death syndrome (S IDS) from changes of pulmonurry surfactant. Methods By means of thin-layer ckromatography technique, surfactant in whole lung specimens of 10 infants with SIDS and 10 control infants without SIDS (dead of nonrespiratory diseases ) were examined qualitatively and quantitatively. Results Eleven components in pulmonary surfactant were examined qualitatively, including lysophosphatidylcholine , sphingomyelin , phosphatidylcholine , phosphatidylserine , phosphatidylinositol , phos phatidylethanolamine , phosphatidylglycerol , diphosphatidylylycerol , phosphatidic acid, cholesterol and neutral lipids. Quantitative examination showed that the amount of surfactant of whole lung specimens in sudden death group [-(8.9±1.0) rng/g wet lung weight] was significantly less than that in control group [-(12. 6±1.4) mg/g uet lung weight, P<0. 01]. Qualitative variance showed that the percentages of phosphatidylcholine (49. 4 % ± 2. 0 % ) and phosphatidylylycerol ( 2. 6 % ± 0. 7 % ) decreased markedly in sudden death group compared with those in control group (61.5 % ± 3. 0 % and 4.3 % ±1. 5%, P < 0. 01 ). Conclusion Before death there is serions defect on metabolism of pulmonary surfactant in sudden death infants, with the amount decreasing and the ratio of its components being disturbed, which is one of the important pathogenies of SIDS.