The Inter-dependence of the Limbs of Feedback Loops Affects the Regulation and Homeostasis of Multiple Physiological Systems.

Abstract

Abstract The fundamental models of physiological regulation and homeostasis remain uncertain and controversial. We aimed to derive quantitative evidence regarding these models from the study of population data of balance points of different parameters and their respective controlling hormones in terms of the slopes of correlations between parameters and controlling hormones, and the slopes of derived estimates of the physiological responses of parameters to their respective regulating hormones. Our simulations showed that changes to the population distribution of, or dependence between, feedback loop limbs alter these slopes of population data derived correlations and estimates in specific ways. Our corresponding empirical findings were similar across multiple systems and support a general model of regulation whereby the balance points of parameters are generated peripherally under the influence of feed-back loops, both limbs of which may interdependent. This interdependence potentially bestows evolutionary homeostatic and regulatory advantages.