Abstract: Kunming mouse was chosen as the experimental animal. The levels of DOPA,DA,NE and EP in brain tissue were measured by high-performance liquid chromatography under acute repetitive hypoxia. As compared with the group Aof blank control without exposed to hypoxia ,group B of experimental control was exposured to hypoxia only once ,and group D of another experimental control was exposed acutely and repetitively to hypoxia for 4 times and then fed for 2 days, the levels of DAincreased significantly and that of DOPA,NE decreased markedly in experimental animals, group C ,acutely and repetitively exposed to hypoxia for 4 times; while the levels of catecholamines were similar between group A and D. There was no significant differences. The results indicated that catecholamines in brain might be involved in the development of tolerance in animals exposed to acute and repetitive hypoxia ,and the process might be a fast reversible response.

Key words: repetitive hypoxia, catecholamines, HPLC