Primate circadian rhythms during spaceflight: results from cosmos
2044 and 2229.
Fuller, Charles A., Tana M. Hoban-Higgins, Vladimir Y Klimovitsky,
David W. Griffin, and Alexei M. Alpatov.
SECTION OF NEUROBIOLOGY, PHYSIOLOGY AND BEHAVIOR and CALIFORNIA
REGIONAL PRIMATE RESEARCH CENTER, UNIVERSITY OF CALIFORNIA, DAVIS, CA
95616-8519 and Institute of Biomedical Problems, Moscow, Russia
APStracts 3:0176A, 1996.
The circadian timing system (CTS) coordinates an animal's physiology
and behavior, both internally and with the 24 hour day. Previous
studies have suggested that the CTS is sensitive to changes in
gravity. To examine this question, the expression of the CTS of four
juvenile male rhesus macaques (Macaca mulatta) were studied in space.
These animals were flown on the COSMOS 2044 and 2229 missions.
Activity, heart rate and axillary and brain (2229) temperatures were
recorded. In both flights, the subjects exhibited delays in the
phasing of their temperature rhythms and a decrease in mean heart
rate compared to ground control studies. These data are in support of
other studies which demonstrate that the CTS is sensitive to changes
in the gravitational environment. Further, the data also support the
concept of a multioscillator organization of the primate CTS due to
the differential responses of the rhythms measured.
Received 28 December 1994; accepted in final form 4 December
1995.
APS Manuscript Number A1357-4.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 16 April 96