A MODEL OF CENTRAL REGULATION IN CARDIOVASCULAR VARIABILITY
心血管变异性的中枢调节数学模型

A mathematical model of cardiovascular variability was developed to evaluate the influence of central regulation on cardiovascular variability in this paper. The model includes 1) the simplest hemodynamic formula, 2) the regulation of heart rate by sympathetic and parasympathetic efferents, 3) baroreceptor reflex, and 4) the central cardiovascular activity influenced by baroreflex and relayed signals from higher level of central nervous system. The simulation of the model showed as follows: 1) the three main spectral components of cardiovascular variability which are coincident with clinical measurement, 2)the same spectral peaks existed in the spectra of both sympathetic and parasympathetic efferents, 3) the sigmoid curve of baroreceptor reflex and its relationship with central nervous activity, and 4) the circadian of cardiovascular variability. The model simulated the main characteristic of cardiovascular variability successfully. The results indicate that the central nervous activity plays an important role in the regulation of cardiovascular variability.