The effect of acute hypoxia with hypercapnia on the content of monoamines in symmetrical brain structures of male BALB/c mice

Changes in activity of neurotransmitter monoamines and their metabolites have been investigated in the right and left brain hemispheres of male BALB/c mice after acute hypoxia with hypercapnia. This condition is characterized by a simultaneous decrease in O2 tension (hypoxia) and increased levels of CO2 (hypercapnia) in the blood and/or other tissues. The concentrations of dopamine, serotonin and their metabolites (dihydroxyphenylacetic, homovanillic and 5-hydroxyindole acetic acids) were measured in the brain cortex, hippocampus and striatum of the right and the left hemispheres by the HPLC method. In control mice (which were not exposed to hypoxia with hypercapnia) a higher concentration of serotonin was detected only in the cortex of the left hemisphere. The asymmetry in the dopamine level was not registered in all structures studied. Acute hypoxia with hypercapnia decreased the striatal dopamine level as well as serotonin levels in the hippocampus and brain cortex. Hypoxia with hypercapnia caused a decrease in dopamine metabolites in the striatum and brain cortex; however, in the right brain cortex both dopamine metabolites decreased, while in the left brain cortex only a decrease in the level of dihydroxyphenylacetic acid was found. Serotonin metabolism decreased in all brain structures of mice exposed to hypoxia with hypercapnia. It is concluded that the brain serotoninergic system is more sensitive to acute hypoxia with hypercapnia than the dopaminergic system. © 2014, Pleiades Publishing, Ltd.