TY - JOUR T1 - LSC 2012 abstract - Repair of the very immature lung following brief, injurious mechanical ventilation commences within 24 hours JF - European Respiratory Journal JO - Eur Respir J VL - 40 IS - Suppl 56 SP - P823 AU - Nadine Brew AU - Stuart Hooper AU - Megan Wallace AU - Richard Harding Y1 - 2012/09/01 UR - http://erj.ersjournals.com/content/40/Suppl_56/P823.abstract N2 - Background: Very preterm infants often require mechanical ventilation (MV). This intervention can cause lung injury that contributes to bronchopulmonary dysplasia. To investigate mechanisms of injury and repair in we have developed a novel method of ventilating the lungs of fetal sheep. Using this model MV-induced injury resolves within 15d, but it is not known when repair starts.Methods: Pregnant sheep at 110d and 125d gestational age (GA; term=147dGA) underwent aseptic surgery in which the fetal trachea was intubated and fetal lungs ventilated for 2h with an injurious MV protocol. Ewes and fetuses remained healthy until necropsy, performed 1d later. Unventilated fetuses were controls, n=6.Results: Following MV, severe lung injury was present at 1d. At 1d potential repair genes (metallothionein and urokinase receptor) mRNA levels were increased in MV lungs at both stages of development. There was no difference in the mRNA levels of early response genes (CTGF, CYR-61, and EGR-1) and inflammatory genes (IL-1β, IL-6, IL-8 and TNFα).Conclusions: Following MV injury, repair processes, commencing with normalisation of early response and inflammatory gene expression and the activation of repair genes, occurs within 24h. ER -