急性肺损伤新生大鼠血清及支气管肺泡灌洗液CC16的变化及意义

目的 探讨急性肺损伤(ALI)早期Clara细胞蛋白CC16的变化及意义.方法 70只健康新生SD大鼠随机分为无菌生理盐水对照组(NS组)及内毒素急性肺损伤组(LPS组,又按注射LPS后处死时间分为7个亚组).LPS组新生大鼠经腹腔注射5 ms/kg LPS,注射后按时间点收集肺组织标本行病理学观察及测定肺湿/干重比值,并收集血清.另取70只健康新生SD大鼠按上述方法分组(NS组及LPS组),收集支气管肺泡灌洗液(BALF),以双抗体夹心ELISA法检测血清及BALF中的CC16含量变化.结果 LPS注射0.5 h后新生大鼠即出现针尖样肺出血,随着时间延长,从局灶性向弥漫性发展;注射2、4 h新生大鼠肺湿/干重比明显增高,差异有非常显著性(P＜0.01),之后回落;BALF中CC16水平在注射LPS后迅速下降,各时点较NS组差异有非常显著性(P＜0.01);血清中CC16水平较NS组上升.以LPS 4 h达高峰,8、16 h组较前下降,但较NS组差异仍有非常显著性(P＜0.01).结论 ALI早期BALF与血清CC16浓度即发生改变,BALF中CC16下降,血清中CC16上升,血清CC16浓度与肺泡上皮及血管内皮完整性相关,血清CC16可作为早期诊断ALI的外周性生物学标志物.

Changes and significance of CC16 in BALF and serum of neonatal rats with acute lung Injury

Objective To investigate Clam cell secretory protein(CC16) change of acute lung injury in neonatal rats.Methods The seventy newborn SD rats were randomly divided into normal saline pretreated group (NS group) and LPS group.The newborn SD rats in LPS group were redivided into 7 subgroup according to the sacrificed time after LPS injection.Lung injury models in neonatal rats were established via intraperitoneal injection of 5 mg/kg LPS.The pathological changes were observed under microscopy,Wet/dryratio were examined.BALF were collected in other seventy newborn rats.CC16 in serum and BALF were detected using enzyme-linked immunoabsorbent assay(ELISA).Results Half-hour following LPS administration to neonatal rats,lung hemorrage was observed,these changes aggravated with time after LPS administration.Wet/dry ratio in neonatal rats at 2～4 hours after LPS administration were significantly increased (P＜0.01),then decreased.The contents of CC16 in BALF were significant lower after the injection of LPS.Significant differences were observed in the contents of CC16 in BALF between the NS and LPS group(P＜0.01).The contents of CC16 in serum in LPS group were higher as compared to NS group (P＜0.01).In LPS group CC16 expression peaked at 4 hours,then decreased at 8 and 16 hours.Conclusion The contents of CC16 in BALF and serum changed in early stage of All,decreased in BALF,whereas increased in serum.The determination of CC16 in serum is a sensitive marker reflecting the integrity of alveolar epithelium and vascular endothelial cell in early stage of ALI.