The Influence of Influenza Virus A on Alveolar Fluid Clearance in Rat Lungs / 中国医科大学学报

ABSTRACT

Objective To investigate the influence of influenza virus A（H1N1,A/PR/8/34 strain）on alveolar fluid clearance（AFC）in vivo and the effects of β1-adrenergic agonist on AFC in rat lungs infected by H1N1.Methods Fortyfive rats were divided into control group（n =12）,H1N1 infection group（the rats were infected with influenza virus strain A/PR/8/34,n =18）,β1-adrenergic agonist groups（the rats were administrated with β1-adrenergic agonist after HIN1 infection,n =15）.AFC was estimated by the progressive increase in the albumin concentration over 30 minutes.The activity of cAMP and cGMP in the lung tissues of control,H1N1 infection and β1-adrenergic agonist groups was measured.Results The infection with H1N1 resulted in a decline in AFC 9.15±1.01% vs control group 17.25±1.01% and increased lung water content（W/D was 6.77±0.13 vs control group 4.99±0.02）.H1N1-mediated inhibition of AFC could be reversed to 14.41±1.41% by the administration of β1-adrenergic agonist denopamine.H1N1 infection increased cGMP levels 7.34±0.40 pmol·mg-1· mg-1 vs control group 5.10±1.88 pmol·mg-1·mg-1 and decreased cAMP levels 1.43±0.06 nmol·mg-1·mg-1 in lung tissues compared with control group.β1-agonist denopamine reversed the level of cAMP to 2.06±0.16 nmol·mg-1·mg-1 and cGMP to 6.16±1.36 pmol·mg-1·mg-1.Conclusion H1N1 infection decreased AFC and increased lung edema.β1-agonist denopamine could reverse AFC and the ratio of cAMP/cGMP in H1N1 infected lung tissues.β1-agonist might regulate AFC through the pathway of cAMP-PKA.