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Updated: Jun 18, 2026
10:36
Measurements of Physiological Stress Responses in C. Elegans
Published on: May 21, 2020
Environmental stress: approximate entropy approach revisited.
Tatjana Loncar-Turukalo1, Dragana Bajic, Olivera Sarenac
1Faculty of Technical Sciences, University of Novi Sad, Serbia. tatjana.turukalo@ktios.net
Summary
This study used the Approximate Entropy (ApEn) method to analyze heart rate variability in rats under stress. Results reveal how stress complexity impacts recovery, offering insights into chronic stress effects.
Area of Science:
- Physiology
- Cardiovascular Research
- Stress Physiology
Background:
- Environmental stress significantly impacts physiological responses.
- Understanding stress-induced changes in heart rate variability is crucial for assessing health outcomes.
- Previous research highlights the need for quantitative methods to analyze complex physiological signals.
Purpose of the Study:
- To quantify the complexity of pulse interval (PI) responses to acute and chronic environmental stress (shaker and restrain) in Wistar and Borderline Hypertensive Rats (BHR).
- To evaluate the performance of the Approximate Entropy (ApEn) method for analyzing stress-induced changes in PI.
- To gain insights into the consequences of chronic stress exposure on physiological recovery.
Main Methods:
- Radiotelemetry was used to record pulse intervals (PI) in male Wistar and Borderline Hypertensive Rats (BHR).
- Animals were subjected to acute and chronic environmental stressors: shaker and restrain stress.
- The Approximate Entropy (ApEn) method was applied to quantify the complexity of PI responses and recovery patterns.
Main Results:
- The Approximate Entropy (ApEn) method demonstrated effectiveness in characterizing the complexity of pulse interval (PI) responses to different stress paradigms.
- Distinct patterns of PI complexity were observed between acute and chronic stress exposures.
- Analysis revealed variations in the duration and complexity of recovery periods post-stress.
Conclusions:
- The ApEn approach provides a valuable tool for quantifying physiological complexity in response to environmental stress.
- Chronic stress exposure appears to alter the complexity of cardiovascular regulation and recovery.
- Findings contribute to a deeper understanding of the physiological impact of prolonged stress.
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