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Updated: Aug 19, 2026

Echocardiographic Assessment of Cardiac Anatomy and Function in Adult Rats
Published on: December 13, 2019
The ontogeny of heart period patterning in the rat
Abstract:
Heart period, heart period variability, and respiration frequency were observed and compared longitudinally in rats from birth to 24 days of age. In addition, V, a quantification of respiratory sinus arrhythmia derived via spectral analysis of the heart period pattern, was observed. It was hypothesized that these heart period parameters would be differentially sensitive to the neural control of the heart and would, therefore, reflect different developmental patterns. Heart period and heart period variability indicated developmental patterns consistent with the literature. The ontogeny of V suggests that it may represent the developmental pattern of tonic vagal influences on the heart.
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