Simultaneous determination of 3,4-dihydroxyphenylacetic acid and homovanillic acid in milligram amounts of rat striatal tissue by gas-liquid chromatography

Simultaneous determination of the major metabolites of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in rat striatum has been achieved by gas-liquid chromatography. Striatal tissue from one rat was homogenized in IN HCl and one-tenth of the sample extracted with ethyl ether. After evaporation of the ether, the residue was reacted with a combination of 1-chloro-1,1,3,3,3-pentafluor-2-propanol and pentafluoropropionic anhydride followed by reaction with pentafluoropropionic anhydride. The derivatives were chromatographed on a 3% JXR column and quantitated using electron capture detection. The propionic homologs of DOPAC and HVA served as internal standards. The steady state levels of DOPAC and HVA were found to be 0.90 μg/gm±0.21 S.D. (N=12) and 0.66 μg/gm±0.16 S.D. (N=12) respectively.