Abstract: Antarctic Dome A is characterized by a multitude of environmental stressors. The effects of the extreme cold and hypoxic environment of Dome A on the catecholamines and myocardial enzyme of expeditioners were investigated. Blood samples from 25 male members of the 29th Chinese Antarctic inland expedition were collected upon departure from Shanghai, during an 18-day stay at Dome A, and upon return to Shanghai. Plasma levels of norepinephrine, epinephrine, dopamine, and high-sensitivity C-responsive protein (hsCRP), as well as serum levels of creatine kinase MB (CK-MB) and cardiac troponin I (cTnI), were measured. Compared with departure, epinephrine and CK-MB levels displayed an increasing trend at Dome A, but did not differ significantly, while dopamine levels increased significantly (P＜0.05). Epinephrine levels decreased significantly (P＜0.01), while dopamine levels increased significantly (P＜0.05), upon return to Shanghai. Compared with the departure (P＜0.01) and Dome A levels (P＜0.01), CK-MB levels decreased significantly upon return to Shanghai. cTnI, hsCRP, and norepinephrine levels did not change significantly at different time points. Pearson’s correlation analysis showed that the CK-MB and epinephrine levels were significantly positively correlated (r=0.285*, P<0.05). These data suggest that there might be adaptive compensatory changes in the myocardium of Chinese Antarctic inland expeditioners, although no pathological injury was found upon their return to Shanghai. Serum levels of myocardial enzymes were closely related to the neuroendocrine regulation of catecholamines. Studies of future expeditions are needed to explore the underlying mechanism.

Key words: Antarctic, Dome A, Hypoxia, Catecholamines, Myocardial enzyme