Bursting Ca²⁺ Oscillations and Synchronization in Coupled Cells

A mathematical model proposed by Grubelnk et al. Biophys. Chem. 94 (2001) 59 is employed to study the physiological role of mitochondria and the cytosolic proteins in generating complex Ca²⁺ oscillations. Intracellular bursting calcium oscillations of point--point, point--cycle and two-folded limit cycle types are observed and explanations are given based on the fast/slow dynamical analysis, especially for point--cycle and two-folded limit cycle types, which have not been reported before. Furthermore, synchronization of coupled bursters of Ca²⁺ oscillations via gap junctions and the effect of bursting types on synchronization of coupled cells are studied. It is argued that bursting oscillations of point--point type may be superior to achieve synchronization than that of point--cycle type.