Experimental Brain Research

, Volume 232, Issue 8, pp 2591–2599

Provocative motion causes fall in brain temperature and affects sleep in rats

Authors

  • Flavia Del Vecchio
    • Department of Biomedical and NeuroMotor SciencesAlma Mater Studiorum University of Bologna
    • School of Biomedical Sciences and PharmacyUniversity of Newcastle
  • Matteo Cerri
    • Department of Biomedical and NeuroMotor SciencesAlma Mater Studiorum University of Bologna
  • Marco Luppi
    • Department of Biomedical and NeuroMotor SciencesAlma Mater Studiorum University of Bologna
  • Roberto Amici
    • Department of Biomedical and NeuroMotor SciencesAlma Mater Studiorum University of Bologna
Research Article

DOI: 10.1007/s00221-014-3899-8

Cite this article as:
Del Vecchio, F., Nalivaiko, E., Cerri, M. et al. Exp Brain Res (2014) 232: 2591. doi:10.1007/s00221-014-3899-8

Abstract

Neural substrate of nausea is poorly understood, contrasting the wealth of knowledge about the emetic reflex. One of the reasons for this knowledge deficit is limited number and face validity of animal models of nausea. Our aim was to search for new physiological correlates of nausea in rats. Specifically, we addressed the question whether provocative motion (40-min rotation at 0.5 Hz) affects sleep architecture, brain temperature, heart rate (HR) and arterial pressure. Six adult male Sprague–Dawley rats were instrumented for recordings of EEG, nuchal electromyographic, hypothalamic temperature and arterial pressure. Provocative motion had the following effects: (1) total abolition of REM sleep during rotation and its substantial reduction during the first hour post-rotation (from 20 ± 3 to 5 ± 1.5 %); (2) reduction in NREM sleep, both during rotation (from 57 ± 6 to 19 ± 5 %) and during the first hour post-rotation (from 56 ± 3 to 41 ± 9 %); (3) fall in the brain temperature (from 37.1 ± 0.1 to 36.0 ± 0.1 °C); and (4) reduction in HR (from 375 ± 6 to 327 ± 7 bpm); arterial pressure was not affected. Ondansetron, a 5-HT3 antagonist, had no major effect on all observed parameters during both baseline and provocative motion. We conclude that in rats, provocative motion causes prolonged arousing effects, however without evidence of sympathetic activation that usually accompanies heightened arousal. Motion-induced fall in the brain temperature complements and extends our previous observations in rats and suggests that similar to humans, provocative motion triggers coordinated thermoregulatory response, leading to hypothermia in this species.

Keywords

Provocative motionMotion sicknessSleepBrain temperatureCardiovascular

Copyright information

© Springer-Verlag Berlin Heidelberg 2014