Open AccessAn improved method for detecting torpor entrance and arousal in a mammalian hibernator using heart rate data
Author(s) -
Amanda D. V. MacCannell,
Ethan Jackson,
Katherine E. Mathers,
James F. Staples
Publication year - 2018
Publication title -
journal of experimental biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.367
H-Index - 185
eISSN - 1477-9145
pISSN - 0022-0949
DOI - 10.1242/jeb.174508
Subject(s) - torpor , heart rate , arousal , hibernation (computing) , metabolic rate , cardiology , biology , medicine , computer science , thermoregulation , neuroscience , blood pressure , algorithm , state (computer science)
We used ECG telemeters to measure the heart rate of hibernating Ictidomys tridecemlineatus. An increase in heart rate from 2.2 to 5 bpm accurately identified arousal from torpor before any change in body temperature was detected. Variability in raw heart rate data was significantly reduced by a forward-backward Butterworth low-pass filter, allowing for discrete differential analysis. A decrease in filtered heart rate to 70% of maximum values in interbout euthermia (from approximately 312 to 235 bpm) accurately detected entrance into torpor bouts. At this point body temperature had fallen from 36.1oC to only 34.7oC, much higher than the 30oC typically used to identify entrance. Using these heart rate criteria advanced detection of entrance and arousal by 51.9 and 76 minutes, respectively, compared with traditional body temperature criteria. This method will improve our ability to detect biochemical and molecular markers underlying these transition periods during which many physiological changes occur.