Cardiovascular function and autonomic regulation in urethane-anesthetized and conscious mice
Anastasiia Vasileva1,2, Laura D M Flores1, Mikhail Vasilyev2
1Department of Health and Human Physiology, University of Iowa, Iowa City, Iowa, United States.
Summary
Urethane anesthesia in mice significantly impacts cardiovascular function, decreasing blood pressure and heart rate variability while affecting oxygen saturation. Supplemental oxygen partially restores oxygen levels but does not reverse hypotension.
Area of Science:
- Physiology
- Anesthesiology
- Cardiovascular Research
Background:
- Urethane is a common anesthetic in murine models, but its cardiovascular effects are poorly understood due to inconsistent data.
- Existing literature lacks comprehensive data on urethane's impact on heart rate, blood pressure, and oxygen saturation in mice.
- Variability in previous studies necessitates a clearer understanding of urethane's physiological consequences.
Purpose of the Study:
- To investigate the cardiovascular effects of urethane anesthesia in C57BL/6J mice.
- To assess the impact of supplemental oxygen during urethane anesthesia on cardiovascular parameters.
- To evaluate heart rate, arterial oxygen saturation, blood pressure, and heart rate variability under different anesthetic conditions.
Main Methods:
- Literature review to identify existing data gaps on urethane's cardiovascular effects in mice.
- Physiological measurements in conscious, urethane-anesthetized, and urethane-anesthetized with supplemental oxygen groups.
- Assessment of blood pressure, heart rate, arterial oxygen saturation, and heart rate variability using time, frequency, and M-curve analyses.
Main Results:
- Urethane anesthesia increased heart rate and significantly reduced arterial blood pressure and heart rate variability.
- Urethane decreased arterial oxygen saturation, which was improved by supplemental oxygen.
- Supplemental oxygen did not prevent hypotension induced by urethane; no sex-specific effects were observed.
Conclusions:
- Urethane anesthesia profoundly impacts mouse cardiovascular function, affecting blood pressure, heart rate, oxygen saturation, and heart rate variability.
- Caution is advised when using urethane, and monitoring cardiovascular parameters is crucial.
- This study introduces M-curve analysis for heart rate-independent variability assessment in rodents.
