|
|
||||||||
AJP - Regulatory, Integrative and Comparative Physiology, Vol 254, Issue 1 109-R116, Copyright © 1988 by American Physiological Society
ARTICLES |
M. Horowitz and S. Samueloff
Department of Physiology, Hadassah School of Dental Medicine, Hebrew University, Jerusalem, Israel.
The effect of thermal dehydration (37 degrees C) on the integrated response of the circulation was studied in conscious laboratory rats and in the desert species Psammomys obesus, the latter being studied prior to and following acclimation to heat. Cardiac output (CO) and its distribution were measured using labeled microspheres with the reference organ technique. At low dehydration (7-9% body wt loss) rats showed peripheral vasodilation coincidentally with splanchnic vasoconstriction, whereas the desert species exhibited an increased CO and peripheral vasodilation with no change in splanchnic blood perfusion. At severe dehydration (10-18% body wt loss), closure of skin arteriovenous anastomoses together with splanchnic vasodilation was observed in both species. These changes were discussed in relation to plasma volume conservation mechanism and its deterioration. Acclimation to heat resulted in no change in CO, whereas blood flow to splanchnic and skin capillaries increased remarkably. Dehydration in heat-acclimated P. obesus (5-10% body wt loss) brought about a significant fall in CO. However, most organs maintained relatively stable blood flow. This might contribute to better survival during heat stress.
This article has been cited by other articles:
![]() |
A. Maloyan and M. Horowitz beta -Adrenergic signaling and thyroid hormones affect HSP72 expression during heat acclimation J Appl Physiol, July 1, 2002; 93(1): 107 - 115. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Mirit, C. Gross, Y. Hasin, A. Palmon, and M. Horowitz Changes in cardiac mechanics with heat acclimation: adrenergic signaling and SR-Ca regulatory proteins Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2000; 279(1): R77 - R85. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. S. Moran, M. Horowitz, U. Meiri, A. Laor, and K. B. Pandolf The physiological strain index applied to heat-stressed rats J Appl Physiol, March 1, 1999; 86(3): 895 - 901. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. C. Looft-Wilson, R. D. Matthes, and C. V. Gisolfi Heat acclimation does not alter rat mesenteric artery response to norepinephrine J Appl Physiol, February 1, 1999; 86(2): 536 - 540. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |