Power spectral analysis of arterial blood pressure in mice: comparison between normal and endothelin-1 gene knocked out mice

In mice heterozygous for endothelin-1 gene mutation and wild-type littermates power spectrum of systolic arterial pressure (SAP) was determined in a conscious stare by forward-backward autoregressive model with maximum entropy method. It was composed of low (LF) and high frequency components (HF). LF reflected sympathetic vasoconstrictor activity, whereas HF was inversely related to respiratory movement. In ET-1 heterozygous mice LF and HF were both significantly elevated than in wild-type mice. The authors conclude that power spectral analysis is a useful mathematical tool to study the autonomic cardiovascular control and respiration in mice and that sympathetic vasoconstrictor activity was increased in ET-1 heterozygous mice. The latter finding may account for observed elevation of arterial pressure (AP) in these mutant mice.