Abstract: | Hypoxic and low-temperature effects on the thermal regulation and the content of catecholamines (epinephrine--E and norepinephrine--NE) in mice have been compared. Continuous and repeated hypoxia brought about a significant drop of the rodent body temperature and heat content. Found was a significant elevation of catecholamines in the pituitary and adrenal tissues, and blood plasma with E prevalence after the continuous exposure. Repeated stimulus resulted in a more pronounced effect. Exception was the adrenal tissue where enhanced E and NE secretion into blood was noted. The uninterrupted and repeated cold conditions were also responsible for heat release. Continuous exposure to low temperature increased NE and decreased insignificantly E in blood and adrenal. Multiple stimulation increased sharply catecholamines concentration in blood plasma with the dominance of epinephrine in the pituitary gland, and norepinephrine in the adrenal. |