Dynamic Characteristics Of Nitric Oxide And The Regulating Model Of MAPK In Taxus Cuspidata Cells Under Shear Stress

The effects of shear stress on nitric oxide (NO) and mitogen-activated protein kinase (MAPK) in Taxus cuspidata cells were investigated in a membrane-Couette. The changes of NO and cell redox, the robustness of H2O2 and MAPK regulating models in Taxus cuspidata under shear stress were investigated. We attempted to analyze the dynamic characteristic of signal regulating models by the model robustness.Changes and the physiological role of NO in Taxus cuspidata under shear stress were investigated. NO concentration in cells reached maximum 5h after shear stress. NO and other nitrogen species inhibited the glutathione S-transferase (GST) activity. The suppression of GST was useful for keeping the GSH content and cell redox. The role of NADPH in ascorbate- glutathione (ASC-GSH) cycle and in AOS elimination was analyzed quantificationally by the metabolic model of AOS elimination. The results showed that ASC and GSH were depleted in the early stage under shear stress. NADPH was required for AOS elimination for long stress. The cell redox would turn to oxidized state while ASC and GSH were oxidized since NADPH was depleted.The proportion, integration and differentiation regulating conception were used in H2O2 regulating model. The genaration and elimination process were regarded as proportional and integral or differential regulation, respectively. The dynamic change of H2O2 was simulated by Simulink using different model. The results showed that the negative feedback model with integrator was according with the experiments of H2O2. The robustness of the MAPK model was analyzed. Huang-Ferrell model with negative feedback control was consistant with the Kholodenko model. The two models have double steady-state respectively and the oscillation property was occurred at special range. The oscillation occurred while the reactive rate of MAPKKK phosphating or MAPK concentration was increased. Periodical change of E1 which activated MAPKKK phosphating caused oscillation in MAPK-PP, which was similar to the above models. The multiresolution analysis was used to discriminate the dynamic properties of H2O2 and MAPK-PP. The dynamic characteristics at different conditions were distinguished at the two-demensions.The dissolve oxygen was compared between conventional type and membrane-Couette. The results showed that the oxygen concentration cell viability...