small volumes ( 0.05 ml ) of cisterna magna cerebrospinal fluid ( csf ) from 23 neurologically normal horses were analysed for the monoamine neurotransmitters dopamine , norepinephrine , epinephrine , serotonin and their metabolites using high pressure liquid chromatography and electrochemical detection .
C0028351
norepinephrine
C0014563
epinephrine