[Analysis of heart rate variability in assessment of baroreflex sensitivity in anesthetized rats].

Spectral analysis of the heart rate variability can be used as a measure of baroreflex sensitivity in ketamine anesthetized rats. Stimulation of delta1-receptors with phenylephrine (0.01 mg/kg, i.v.) results in a rise of the strength of heart rate regulation, principally in the low frequency band. Maximal deviations of spectral indexes from basal level were observed on 4-8 min for low (0.2-1 Hz) and high (1-3 Hz) frequencies bands and on 10-15 min for very low (0.08-0.2 Hz) frequency band after phenylephrine injection.