Abstract
The classic model of blood pressure regulation by Guyton et al. set a new standard for quantitative exploration of physiological function and led to important new insights, some of which still remain the focus of debate, such as whether the kidney plays the primary role in the genesis of hypertension. Key to the success of this model was the fact that the authors made the computer code freely available and eventually provided a convivial user interface for exploration of model behavior on early microcomputers. Ikeda et al. developed an offshoot of the Guyton model targeting especially the regulation of body fluids and acid–base balance; their model provides extended renal and respiratory functions and would be a good basis for further extensions. In the interest of providing a simple, useable version of Ikeda et al.’s model and to facilitate further such extensions, we present a practical implementation of the model of Ikeda et al., using the ODE solver Berkeley Madonna