Comments:
Decay of internal calcium concentration due to calcium currents and atpase pump. Published in destexhe et al (1993), written by a destexhe nov 1992. Modified by y poirazi for golding et al (1999). Modified by liu for calcium dynamics in rod, 2003. Ancestry is unclear for this model. Animal model is from experiments in this paper. Channel kinetics come from experiments here and formulations in ancestor models.