The role of G protein and protein kinase C mechanical signalling transduction in mandibular condylar chondrocytes / 实用口腔医学杂志

ABSTRACT

Objective: To investigate the expression and distribution of G protein and protein kinase C (PKC) under the mechanical pressure in rabbit mandibular condylar chondrocytes (MCCs) and to study the role of G protein in PKC signalling pathway. Methods:MCCs from two-week-old New Zealand rabbits were cultured. After treatment under continuous pressure of 90 kPa for 60 min or 360 min by hydraulic pressure controlled cellular strain unit, the expression of G?q/11 protein was examined by Western Blot. The expression and distribution of PKC was observed by immunocytochemical staining. Results:Gaq/11 protein in MCCs treated by 90 kPa for 60 min and 360 min was increased by 163.7% and 65.8% respectively(P0.05). PKC in control cells distributed uniformly in the cytoplasm. After been pressed under 90 kPa for 60 min,PKC translocated to the membrane and, partly,into nuclei. When the pressure prolonged to 360 min, PKC distributed uniformly again in cytoplasm. By treatment of G protein inhibitor, the translocation of PKC under 90 kPa of 60 min was not observed. Conclusion:Feasible pressure may promote G protein expression and activate PKC. The activation of PKC signalling pathway is mediated by G protein.