Lighting conditions alter candida albicans-induced sleep responses in rabbits. Toth, Linda A., and James M. Krueger. Departments of Comparative Medicine and Physiology and Biophysics, University of Tennessee, Memphis, TN 38163 USA, Present address: Department of Infectious Diseases, Comparative Medicine Division, St. Jude Children's Research Hospital, 332 N. Lauderdale, Memphis, TN 38101
APStracts 2:0216R, 1995.
To evaluate the influence of light on sleep patterns after microbial challenge, we studied rabbits housed in 12:12 h light:dark (LD), constant light (LL) or constant darkness (DD) before and after intravenous Candida albicans inoculation. Compared to the LD group, uninoculated LL rabbits sporadically increased slow-wave sleep and delta-wave amplitudes during the circadian period previously associated with the dark phase. In contrast, uninfected DD rabbits showed reduced sleep during the circadian period previously associated with the light phase. Inoculation of LD rabbits with Candida approximately 2 h after light onset increased slow-wave sleep and delta-wave amplitudes during h 4-8 postinoculation and reduced these parameters during h 20-46. In contrast, Candida-inoculated LL rabbits demonstrated increased slow-wave sleep for up to 28 h after inoculation, with little subsequent reduction; delta-wave amplitudes were similar to those of LD rabbits. Candida-inoculated DD rabbits demonstrated attenuated increases in slow-wave sleep and delta-wave amplitudes, but the suppression phase was not altered. We conclude that lighting conditions modulate microbially-induced sleep alterations.

Received 15 February 1995; accepted in final form 4 July 1995.
APS Manuscript Number R109-5.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 10 August 1995.