A fixed charge system as a formal model for the behaviour of smooth muscles and the heart.

An extension of the theory of the "fixed charge" controlled "membrane oscillator" is used for simulation of a variety of excitability phenomena in nerves, presso-receptors, smooth muscle and the heart. A central issue is the prediction of water movements across the cell membrane resulting in "swelling" and "shrinkage". The presented "electrohydraulic excitability analog" (EHEA) deals particularly with the generation of action potentials, volume-pressure changes and contractility in response to externally applied mechanical stimuli, i.