Role of arterial baroreflex in producing the 1/f shape of systolic blood pressure and heart rate spectra

In eight conscious cats, the spectral characteristics of systolic blood pressure and heart rate have been estimated before and after surgical opening of the arterial baroreflex obtained by denervation of carotid and aortic baroreceptors. Each spectrum was fitted by the 1/f^α model and the residuals were analyzed to determine which regions of the spectra are reliably described by the model in intact conditions and after baroreflex denervation. The study indicated that the baroreflex plays a primary role in producing the 1/ f^α shape of systolic pressure components at frequencies <0.02 Hz and of heart rate components in a band from 0.2 to 0.05 Hz