Cold-induced Changes in Plasma Catecholamines in Men

Abstract

In order to know a role of sympathetic function in men, 26 nude male subjects were exposed to 10°C or 5°C for 30 min and the changes in energy metabolism and plasma catecholamine levels were studied.
Energy metabolism was elevated by 9.9±2.05 kcal/m²/h and 23.5±3.24 kcal/m²/h after 10°C and 5°C exposure, respectively. Plasma noradrenaline level was also significantly elevated in both ambient temperatures, but there is no difference between the increments in both temperature conditions: 451±141.1 pg/ml in 10°C and 321±72.4 pg/ml in 5°C. There is a positive correlation between the percent increases in plasma noradrenaline and those in energy metabolism after 10°C exposure but not after 5°C exposure.
These results indicate that noradrenaline may be associated with cold-induced thermo-genesis in men.