Phase synchronization and coherence resonance of stochastic calcium oscillations in coupled hepatocytes.
The frequency of free cytosolic calcium concentration ([Ca(2+)]) oscillations elicited by a given agonist concentration differs between individual hepatocytes. However, in multicellular systems of rat hepatocytes and even in the intact liver, [Ca(2+)] oscillations are synchronized and highly coordinated. In this paper, we have investigated theoretically the effects of gap junction permeable to calcium and of the total Ca(2+) channel number located on endoplasmic reticulum on intercellular synchronization. Figures of ratio between mean oscillating frequency of coupled cells describe visually the process of phase-locking. By virtue of a set of phase analysis, we can observe a gradual transition from synchronous behavior to nonsynchronous behavior. Furthermore, a signal-to-noise ratio in two dimensional parameter space (coupling strength-total Ca(2+) channel number) has suggested that, coherence resonance will occur for appropriate noise and coupling.
Wu
Dan
D
Department of Physics and Institute of Biophysics, Central China Normal University, Wuhan, Hubei. wud@phy.ccnu.edu.cn
Jia
Ya
Y
Yang
Lijian
L
Liu
Quan
Q
Zhan
Xuan
X
D000818:Animals; D001683:Biological Clocks / Q000502:physiology*; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling / Q000502:physiology*; D002450:Cell Communication / Q000502:physiology*; D003600:Cytosol / Q000378:metabolism / Q000502:physiology; D004721:Endoplasmic Reticulum / Q000378:metabolism; D017629:Gap Junctions / Q000378:metabolism; D022781:Hepatocytes / Q000378:metabolism*; D008954:Models, Biological; D009991:Oscillometry; D010539:Permeability; D051381:Rats; D013269:Stochastic Processes
D002118:Calcium