Related Experiment Video
Updated: Jul 14, 2026
06:18
Assessing the Autonomic and Behavioral Effects of Passive Motion in Rats using Elevator Vertical Motion and Ferris-Wheel Rotation
Published on: February 7, 2020
Linear acceleration-evoked cardiovascular responses in awake rats
Hong Zhu1, James R Jordan, Steven P G Hardy
1Dept. of Otolaryngology and Communicative Sciences, University of Mississippi Medical Center, Jackson, MS 39216, USA. hozhu@ent.umsmed.edu
Journal of Applied Physiology (Bethesda, Md. : 1985)
|June 9, 2007
Summary
Otolith stimulation from linear motion selectively impacts blood pressure regulation in rats. This study reveals otolith-specific cardiovascular responses mediated by vestibular nuclei, establishing a new rodent model.
Area of Science:
- Neuroscience
- Cardiovascular Physiology
Background:
- Vestibular system regulates blood pressure during postural changes.
- Previous studies lacked selective otolith system investigation due to combined stimulation.
Purpose of the Study:
- Characterize cardiovascular responses to natural otolith stimulation using pure linear motion in awake rats.
- Elucidate the neural mechanisms of otolith-mediated cardiovascular regulation.
Main Methods:
- Subjecting awake rats to linear motion in four directions.
- Measuring blood pressure and heart rate responses.
- Utilizing anesthesia, bilateral labyrinthectomy, baroreceptor denervation, and vestibular nuclei inactivation (muscimol).
Main Results:
- Transient linear motion induced a short-latency increase in mean blood pressure (BP) and a biphasic heart rate (HR) response.
- BP increase was abolished by anesthesia or labyrinthectomy but unaffected by baroreceptor denervation, confirming otolith origin.
- BP response intensity depended on linear acceleration and was independent of visual cues.
- Vestibular nuclei inactivation attenuated the BP response, implicating medial and inferior vestibular nuclei.
Conclusions:
- Demonstrates specific otolith system influences on cardiovascular regulation.
- Establishes the first rodent model for studying otolith-mediated cardiovascular control mechanisms.
