Title: Expression of Matrix Metalloproteinases-2 and -9 in Newborn Rabbits with Hyperoxia Ventilator-induced Lung Injury
Abstract:Objective To investigate the changes and expressions of matrix metalloproteinase(MMP)-2 and MMP-9 in newborn rabbits with hyperoxia ventilator-induced lung injury,to find their probable molecular mech...Objective To investigate the changes and expressions of matrix metalloproteinase(MMP)-2 and MMP-9 in newborn rabbits with hyperoxia ventilator-induced lung injury,to find their probable molecular mechanisms.Methods Sixty newborn rabbits aged 1-5 days were randomized into high peak inspiratory pressure(PIP)group,moderate PIP group and low PIP group to perform hyperoxia ventilation,and then compared with control group without mechanical ventilation(MV).All experimental groups were killed to obtain lung tissues at hours 1,3,and 6 after MV.MMPs-2 and -9 were immunohistochemically stained in lung tissue pathological sections,and the concentration of MMPs-2 and -9 in lung tissue bomogenate was detected by ELISA,and the gene expressions by RT-PCR in lung tissues.Results We found that:① High,moderate and low PIPs made the concentration of MMP-2 increased and the mRNA expression strengthened.There was significant difference between them(F=3.272,P0.05).②The expression of MMP-9 was first down-regulated with low mean concentration.With the ventilation going on,it was regulated gradually up to normal levels.The impacts of different PIPs on MMP-9 changed little(F=0.083,P0.05).③There were positive correlations between MMP-2 and MMP-9,between MMP-2 and -9 and the wet-dry ratio in the same lung tissues,between MMP-2 and -9 and the total white blood cells in broncho-alveolar lavage fluid.Conclusion Within 6-hour MV in new-born rabbits,high levels of oxygen ventilation can up-regulate MMP-2 but down-regulate MMP-9,and the lung mechanical stretch increase MMP-2.MV has influence on syntheses of MMPs.MMPs play an important role in hyperoxia ventilator-induced lung injuries of new-born rabbits.Read More
Publication Year: 2008
Publication Date: 2008-01-01
Language: en
Type: article
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