Physiological and hematological responses to cold exposure in young subjects.
BACKGROUND
In this study we have investigated the effect of cold exposure on young healthy subjects, with particular emphasis on the hematological system.


METHODS
The lightly clothed subjects were seated in a thermally controlled climatic chamber for three hours.


METHODS
One group (control) was exposed to three hours at 28 degrees C, while the other group was first exposed to one hour at 28 degrees C, and then two hours of decreasing temperature, ending at 6 degrees C. Mean body temperature decreased, blood pressure increased, and metabolism increased by 60% in the cold exposure group compared to the control group. Blood samples were taken through an arterial catheter every hour during the exposure, one hour before and 1.5, 3 and 25 hours after the exposure.


RESULTS
Red blood cell counts increased, due to hemo-concentration. In the cold neutrophil counts did not increase during the day, but were stable at a lower level compared to the controls.


CONCLUSIONS
It is suggested that the cold induced decrease in neutrophil count is caused by an activation and increased adhesion of the neutrophils to the endothelial wall. This finding is supported by the cold exposure-induced increases in IL-8 and Thromboxane B2 in LPS-stimulated blood, and an increase in the plasma concentration of P-selectin.
Bøkenes
Lise
L
Department of Medical Physiology, Institute of Medical Biology, Faculty of Medicine, University of Tromsø, Norway. lise@fagmed.uit.no
Alexandersen
Toril E
TE
Tveita
Torkjell
T
Osterud
Bjarne
B
Mercer
James B
JB
D000328:Adult; D001481:Basal Metabolism; D001772:Blood Cell Count; D001794:Blood Pressure; D001831:Body Temperature; D003080:Cold Temperature; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D010829:Physiological Phenomena; D015539:Platelet Activation; D012016:Reference Values