Effect of central cooling in man on pituitary-thyroid function and growth hormone secretion

Publisher Website
Google Scholar
Abstract
In order to determine if central cooling in the human leads to activation of the pituitary-thyroid axis, as has been demonstrated in goats and rats, studies were carried out of pituitary-thyroid function in normal humans following the ingestion of 500 g of cracked ice. The subjects were maintained at thermal neutrality to prevent skin thermoreceptor activation. In 6 normal men, tympanic membrane temperature fell 0.5 C [plus or minus] 0.02 SE, and returned to normal by 60 min. Oxygen consumption measured by spirometry rose in 4 of the 6 subjects, but the mean change for the group was not significant statistically. Plasma TSH measured by radioimmunoassay was not altered by central cooling, and the slight changes in plasma protein-bound iodine, which were observed, were attributable to changes in hemoconcentration. Plasma growthhormone levels were also determined because of the recent demonstration that a variety of stressful stimuli increase growth hormone secretion, butthis hormone also was unaffected by ice ingestion. It was concluded that a brief period of central cooling in man brings about a prompt increase In oxygen consumption in some individuals, but that no significant activation of the pituitary-thyroid axis or of growth hormone secretion was observed under the conditions of this experiment.

This publication has 1 reference indexed in Scilit: