Role of alpha-adrenoceptors in the maintenance of core temperature in XXXX .

@entity1 @entity26 @entity5521 @entity2332
1. Although alpha-adrenoceptor antagonists have been shown to induce @entity2332 in animals, it is unclear whether the primary mechanism is increased heat loss or decreased heat production. Furthermore, studies have not been performed in @entity1 to determine the role of alpha-adrenoceptors in the maintenance of core temperature. 2. alpha-Adrenoceptor blockade was achieved with three doses of @entity5521 given by random assignment on three different study days in five male and five female healthy subjects. Core temperature, mean skin-surface temperature, fingertip capillary blood flow and metabolic heat production were measured. Dose-response curves were plotted for all measured variables, and males and females were compared to identify potential gender differences. 3. Core temperature decreased with all doses of @entity5521 . At the completion of the @entity5521 infusion, the decrease in core temperature was more significant with high-dose (0.3 +/- 0.1 degrees C, P = 0.03) and with medium-dose (0.2 +/- 0.0 degrees C, P = 0.05) @entity5521 than with low-dose @entity5521 (0.1 +/- 0.0 degrees C). The maximum core temperature decrease during the study was more significant with high dose (0.6 +/- 1 degrees C) than with medium (0.3 +/- 1 degrees C, P = 0.04) or low (0.3 +/- 1 degrees C, P = 0.005) doses. Mean skin-surface temperature was increased with all doses. Fingertip blood flow was increased (approximately 60% above baseline) with the medium and high doses, but was unchanged with the low dose. Total body @entity26 consumption was unchanged regardless of dose.(ABSTRACT TRUNCATED AT 250 WORDS)
