[Analysis of rat 24h heart rate variability based on telemetry technology].

In this study ECG signal of unstrained rat was recorded by telemetry device, and heart rate variability (HRV) was analyzed in order to evaluate 24h autonomic nervous activity. The results demonstrated an obvious circadian rhythm in the autonomic nervous activity: sympathetic activity being dominant during wake phase, and parasympathetic activity, dominant during sleep phase. The ratio of the low frequency to high frequency components in HRV power spectrum (LF/HF) fluctuates with the change in the sleep stages. It is concluded that 24h HRV analyses may reveal plentiful information about the behavior of autonomic nervous system and thus facilitate the investigation of its regulating role in physiological and pathological processes.