RESUMO
<p><b>OBJECTIVE</b>To study the changes in activity of phosphatidylinositol 4 kinase (PI 4 kinase), phosphatidylinositol 4 phosphate 5 kinase (PIP 5 kinase) and protein kinase C (PKC) during myocardial ischemia and elucidate the relationship between phosphatidylinositol signal pathways and prolonged myocardial ischemia.</p><p><b>METHODS</b>In vivo an ischemic rat model was used. Activity of PI 4 kinase, PIP 5 kinase and PKC were measured at different times in postischemic heart cells using isotope analysis.</p><p><b>RESULTS</b>The activity of PI kinase, PIP kinase and PKC in the myocardium increased to peak at 1 hour postischemia, with activities 6.1, 3.0 and 4.0 fold over control levels, respectively. Their activities declined to normal levels with time.</p><p><b>CONCLUSION</b>The phosphatidylinositol signal pathway is involved in prolonged myocardial ischemia, but its mechanism needs further study.</p>
Assuntos
Animais , Masculino , Ratos , 1-Fosfatidilinositol 4-Quinase , Metabolismo , Isquemia Miocárdica , Fosfotransferases (Aceptor do Grupo Álcool) , Metabolismo , Proteína Quinase C , Metabolismo , Distribuição Aleatória , Ratos Wistar , Transdução de SinaisRESUMO
Objective:To clone human anti MMP 2 antibodies from semisynthetic phage antibody library.Methods:Panning of semisynthetic phage antibody library against recombinant human MMP 2 was conducted to select specific antibodies.The antigen binding characterastics were analyzed by ELISAs.Results:MMP 2 binding phage antibody clones were obtanied after four rounds of panning,but they all showed binding activity to unrelated ags tested.One clone,AD20,was chosen for further analysis by competitive ELISA.It was found that the binding of AD20 to MMP 2 could be inhibited only by free MMP 2 but not unrelated Ags,while the binding to other Ags could not be inhibited by Ags tested,including MMP 2.Neutralization test demonstrated that AD20 could neutralize the enzymatic activity of MMP 2.Conclusion:A neutralizing human antibody against MMP 2 was obtained from a semisynthetic phage antibody library,which shows bindings with unrelated Ags nonspecifically that may be caused by different binding modes,a phenomenon termed polyreactivity.