RESUMO
Objective To investigate the effect of L-arginine on expression of protein kinase C(PKC)mRNA during pulmonary ischemia and reperfusion injury(PIRI)in the rabbits.Methods Single lung ischemia and reperfusion animal model was used in vivo.The rabbits were randomly divided into three groups(n=9,in each),sham operated group (Sham),PIR group(I-R)and PIR+L-arginine group(L-Arg).Changes of several rariables including malondialdehyde (MDA),superoxide dismutase(SOD),malandialde hyde(MDA),nitril oxide(NO),wet to dry ratio of lung tissue weight(W/D)and index of quantitative assessment(IQA)of histolngic lung injury were recorded at 60 minutes after reperfusion in lung tissue.Meanwhile the location and expression of PKC mRNA were observed.Lung tissue was prepared for light microscopic and electron microscopic observation at 60 minutes after reperfusion.Results In comparison with group I-R,PKC mRNA strongly expressed in intima and extima of small pulmonary artery as well as thin-waU vessels (mostly small pulmonary veins).The average optical density values of PKC-?,?and?mRNA in small pulmonary veins in L-Arg group had significance(all P＜0.01);SOD increased while MDA,W/D and IQA decreased at 60 minutes after reperfusion in lung tissue(P＜0.01 and P＜0.05).A morphologically abnormal changes of the lung tissue,were lessen markedly in L-Arg group.Conclusion L-arginine possess notably protective effects on PIRI in rabbits by activating PKC-?,?and?mRNA expression in lung tissue,raising NO level,dropping oxygen free radical level and decreasing lipid peroxidation.