A model of homeostasis maintenance

Abstract

The paper is aimed to construction of models of mechanisms determining the accuracy and stability of maintenance of target values for internal environment characteristics. The organism is described as an integrated set of physiological systems, namely, the homeostasis maintaining system, the reproductive system, and others. Those systems are joined by a common internal environment and a pool of energy substrate. The accuracy of homeostasis maintenance depends on the power, and the resistance to strong perturbations depends on the functional reserve of the homeostasis maintaining system. A specific feature of the model is the consideration of the dependence of the violation of internal environment characteristics on the current power of the energy metabolism. Experimental data show that the energy cost of maintaining the homeostasis and regeneration exceeds 70% of total energy expenditure of the body and creates most of the load of the system. The energy cost of homeostasis maintenance increases with the growth of the functional reserve and/or the deviation of internal environment characteristics from their target values, which reduces the amount of energy used for regeneration and reproduction. The model describes a physiologically motivated algorithm of adaptive use of functional reserves and energy substrate