https://staging.physiomeproject.org/w/hnielsen/grubelnik_2001 en-us In a mathematical model for simple calcium oscillations [Biophys. Chem. 71 (1998) 125], it has been shown that mitochondria play an important role in the maintenance of constant amplitudes of cytosolic Ca[2+] oscillations. Simple plausible rate laws for [Ca+] fluxes across the inner mitochondrial membrane have been used in this model. Here we show that it is possible to use the same rate laws as a plug-in element in other existing mathematical models and obtain the same effect on amplitude regulation. This result appears to be universal, independent of the type of model and the type of Ca oscillations. We demonstrate this on two models for spiking Ca oscillations [J. Biol. Chem. 266 (1991) 11068; Cell Calcium 14 (1993) 311] and on two recent models for bursting Ca oscillations; one of them being a receptor-operated model [Biophys. J. 79 (2000) 1188] and the other one being a store-operated model [BioSystems 57 (2000) 75]. https://staging.physiomeproject.org/w/hnielsen/grubelnik_2001/@@file/f78690e2f46454aa4ef277c8a5e8eabda2b8759c Added cellML models for 2a, 2b, 3a, 3b, 4a and 4b and clickable sessions. Hanne Nielsen 2011-09-26 https://staging.physiomeproject.org/w/hnielsen/grubelnik_2001/@@file/4dbd2434705828f0e9fc8b28535a2d073131e74c Added file a (minus mitochondria) and b (with mitochondria) based on equations 2 and 1 and 3. Images in ai, svg and png format added alongside HTML file Hanne Nielsen 2011-08-08