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Updated: Jan 20, 2026

Optogenetic Activation of Intrinsic Cardiac Autonomic Neurons in Excised Perfused Mouse Hearts
Published on: March 28, 2025
Symbolic analysis of heart rate fluctuations identifies cardiac autonomic modifications during LPS-induced
José Javier Reyes-Lagos1, Claudia Ivette Ledesma-Ramírez1, Martin Hadamitzky2
1Autonomous University of the State of Mexico (UAEMex), Faculty of Medicine, Toluca, 50180, Mexico.
Abstract:
The present study aimed to compare linear and symbolic dynamics (SD) indices for detecting the autonomic cardiac changes produced by endotoxemia in freely-moving rats. In this context, we analyzed ECG-derived R-R time series in freely moving Dark Agouti rats, which received lipopolysaccharide (LPS, n = 9), or vehicle (V, n = 7). Five minutes R-R time series were assessed every hour up to +12 h and + 24 h post-LPS injection. We found that SD indices showed significant differences at +7 h between V vs. LPS groups and at +9 h between basal levels of LPS (-3 h) and post-LPS injection (pre-LPS vs. post-LPS). In general, SD seems more appropriate than linear indices to evaluate the autonomic changes of endotoxemic rats. Overall, the symbolic parameters detected decreased R-R variability and complexity, which indicate a modification of the autonomic regulation during LPS-induced endotoxemia. This modification is probably related to a reduced activity of the cholinergic anti-inflammatory pathway at the long term.
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