Objective:To investigate the influence of p38MAPK inhibitor SB203580 on osteoblast MC3T3-E1 cells under high glu-cose concentration.Methods:MC3T3-E1 cells were exposed to glucose at 5.5 mmol/L,25.5 mmol/L and 25.5 mmol/L combined with SB203580 respectively.Cell proliferation was analysed by MTT assay,calcified nodules were quantitated by Alizarin Red S stai-ning.Osteogenesis gene(OCN,Runx2)mRNA level was examined by realtime PCR.Results:High glucose decreased cell prolifera-tion(P<0.05),ALP activity(P<0.05),calcified nodule formation and osteogenesis gene expression of MC3T3-E1 cells.SB203580 reversed the down-regulation of osteogenic markers under high glucose,increased the ALP expression but decreased cell proliferation. Conclusion:SB203580 is antagonistic to P38MAPK in the regulation of preliferation and differetiation of MC3T3-E1 cells.

Objective To investigate the expression of c-jun in precancerous lesion and squamous cell carcinoma tissues of hamster buckle pouch mucosa.Methods The models of premalignant and malignant lesions were established in hamster buckle pouch mucosa induced with DMBA.The expressions of c-jun in 23 oral normal mucosa, 22 abnormal epithelial hyperplasia and 29 oral squamous cell carcinoma (OSCC) were measured with immunohistochemical SABC method.Results c-jun mainly expressed in basal cells and prickle cells in normal mucosa,simple and abnormal epithelial hyperplasia,its positive expression was in nucleus.c-jun expressed mainly in various layer cells of OSCC,its positive expression was in nucleus and cytoplasm.There were significant differences of positive expression rate between various groups(?2=13.71,P