After rats were exposed to 5,000 ppm carbon monoxide for 30 minutes, the amounts of catecholamine neurotransmitters in stratum were measured using high performance liquid chromatograph equipped with electrochemical detector. The concentration of dopamine in stratum was significantly decreased after carbon monoxide intoxification, but those of dihydroxyphenylacetic acid, norepinephrine, and epinephrine was not changed. However the pretreatments of Ginseng total saponin and panaxatriol saponin increased the concentrations of dopamine and its acidic metabolites (DOPAC and HVA). Ginseng total saponin also increased the concentrations of norepinephrine and epinephrine. Similar results were obtained from aged rats.