Study On The Time-dependent Expression Of VCAM-1 And VEGF During Acute Lung Injury Induced By High-V_T Mechanical Ventilation Healing In Rabbits

Objective: To explore the time-dependent kinetic change of vascular endothelial growth factor(VEGF) and vascular cell adhesion molecule-1(VCAM-1) during acute lung injury(ALI) by high-V_T mechanical ventilation healing in rabbits for more accurately estimating the time of acute lung injury .Methods: (l)The animal model of acute lung injury induced by high-V_T mechanical ventilation in rabbits was established with the survival rate, the wet/dry ratio and pathological change.(2)The lung tissues were freshly collected from rabbits at different time points after acute lung injury by the standard animal model .Sequentially some empirical methods were carried out. The wet/dry ratio of right upper lung was measured to compare the degree of pneumochysis at each time point. Pathological change was observed by using hematoxylin and eosin (H.E) stain. Immunohistochemical method (SABC) and immunoblotting was employed to detect expression of VCAM-1 and VEGF at protein level.Results: During establishing the animal model of acute lung injury induced by high-V_T mechanical ventilation, the degree of pneumochysis and pathological change was more severe in trial group B (V_T 60ml/kg) than trial group A (V_T 45ml/kg), and non- significant different between trial group C (Vt 68ml/kg) and trial group B. The survival rate of empirical animals in trial group B were higher than trial group C, attaining to 91.67%.Based on the standard animal model, the degree of pneumochysis and pathological change was observed the most severe during 12-24 hour after acute lung injury induced by high-V_T mechanical ventilation. Expression of VCAM-1 started to be...