Studies on the translocation of p38 mitogen-activated protein kinase in cardiomyocytes of nude mice on the stimulation of LPS

Objective: To study the translocation process of p38 mitoggen-activated protein kinase (MAPK)induced by the stimulation of lipopolysaccharide (LPS)for elucidation of the specific sighal transduction mechanism of p38 MAPK in cells Methods:Laser scanning conforal microscope and electron microscopy techniques were used to check the distribution of p38 MAPK in myocardial cells and the effect of lipopolysaccharide on its translocation Results:By the method of immunofluores- cence labeling it was found that p38spread all over the cytosol and nuclei in the quiescent or EGF stimulated cells Follow ing the stimulation of LPS for 30 min the fluorescent intensity in the nuclei of cardiomyocytes was enhanced while that in the cytosol area was reduced It was shown by electron microscope that the diffused p38 MAPK in the cytosol of the quies- cent myocardial cells moved into the nuclei following the treatment of LPS Conclusion: The stimulation fo LPS on myocardi- al cells brought about translocation of p38 MAPK into the nuclei