Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Brain and abdominal temperatures at fatigue in rats exercising in the heat

Brain and abdominal temperatures at fatigue in rats exercising in the heat Abstract We measured brain and abdominal temperatures in eight male Sprague-Dawley rats (350–450 g) exercising voluntarily to a point of fatigue in two hot environments. Rats exercised, at the same time of the day, in three different trials, in random order: rest 23°C, exercise 33°C; rest 23°C, exercise 38°C; and rest 38°C, exercise 38°C. Running time to fatigue was 29.4 ± 5.9 (SD), 22.1 ± 3.7, and 14.3 ± 2.9 min for the three trials, respectively. Abdominal temperatures, measured with intraperitoneal radiotelemeters, at fatigue in the three trials (39.9 ± 0.3, 39.9 ± 0.3, and 39.8 ± 0.3°C, respectively) were not significantly different from each other. Corresponding brain temperatures, measured with thermocouples in the hypothalamic region (40.2 ± 0.4, 40.2 ± 0.4, and 40.1 ± 0.4°C), also did not differ. Our results are consistent with the concept that there is a critical level of body temperature beyond which animals will not continue to exercise voluntarily in the heat. Also, in our study, brain temperature was higher than abdominal temperature throughout exercise; that is, selective brain cooling did not occur when body temperature was below the level limiting exercise. hyperthermia temperature regulation selective brain cooling sleep Footnotes Address for reprint requests: A. Fuller, Dept. of Physiology, Univ. of the Witwatersrand, Medical School, 7 York Rd., Parktown 2193, Johannesburg, South Africa (E-mail: 127andy@chiron.wits.ac.za ). This work was funded by the Foundation for Research Development, South Africa. Copyright © 1998 the American Physiological Society Related articles THIS MONTH IN THE JOURNAL : This Month in the Journal J Appl Physiol March 1, 1998 84 : 759 - 760 Full Text Full Text (PDF) http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Applied Physiology The American Physiological Society

Brain and abdominal temperatures at fatigue in rats exercising in the heat

Download PDF
8 pages

Loading next page...
 
/lp/the-american-physiological-society/brain-and-abdominal-temperatures-at-fatigue-in-rats-exercising-in-the-4VbMadpYF8

References

References for this paper are not available at this time. We will be adding them shortly, thank you for your patience.

Publisher
The American Physiological Society
Copyright
Copyright © 2011 the American Physiological Society
ISSN
8750-7587
eISSN
1522-1601
Publisher site
See Article on Publisher Site

Abstract

Abstract We measured brain and abdominal temperatures in eight male Sprague-Dawley rats (350–450 g) exercising voluntarily to a point of fatigue in two hot environments. Rats exercised, at the same time of the day, in three different trials, in random order: rest 23°C, exercise 33°C; rest 23°C, exercise 38°C; and rest 38°C, exercise 38°C. Running time to fatigue was 29.4 ± 5.9 (SD), 22.1 ± 3.7, and 14.3 ± 2.9 min for the three trials, respectively. Abdominal temperatures, measured with intraperitoneal radiotelemeters, at fatigue in the three trials (39.9 ± 0.3, 39.9 ± 0.3, and 39.8 ± 0.3°C, respectively) were not significantly different from each other. Corresponding brain temperatures, measured with thermocouples in the hypothalamic region (40.2 ± 0.4, 40.2 ± 0.4, and 40.1 ± 0.4°C), also did not differ. Our results are consistent with the concept that there is a critical level of body temperature beyond which animals will not continue to exercise voluntarily in the heat. Also, in our study, brain temperature was higher than abdominal temperature throughout exercise; that is, selective brain cooling did not occur when body temperature was below the level limiting exercise. hyperthermia temperature regulation selective brain cooling sleep Footnotes Address for reprint requests: A. Fuller, Dept. of Physiology, Univ. of the Witwatersrand, Medical School, 7 York Rd., Parktown 2193, Johannesburg, South Africa (E-mail: 127andy@chiron.wits.ac.za ). This work was funded by the Foundation for Research Development, South Africa. Copyright © 1998 the American Physiological Society Related articles THIS MONTH IN THE JOURNAL : This Month in the Journal J Appl Physiol March 1, 1998 84 : 759 - 760 Full Text Full Text (PDF)

Journal

Journal of Applied Physiology – The American Physiological Society

Published: Mar 1, 1998

There are no references for this article.