Elevation of plasma salsolinol sulfate in chronic alcoholics as compared to nonalcoholics

This report describes a radioenzymatic assay for the measurement of salsolinol and dopamine sulfate levels in plasma. It is based on a sulfatase-catalyzed hydrolysis of the sulfoconjugates followed by catechol-O-methyltransferase and [methyl-3H]-S-adenosylmethionine-catalyzed O-methylation of the resulting free salsolinol and dopamine. Rapid thin-layer chromatographic separation of the formed labeled metabolites attributed to the specificity of the differential enzymatic assay of salsolinol and dopamine. This assay was used to study plasma salsolinol and dopamine levels in a group of adult males (n = 36) serving as controls and a group of hospitalized chronic alcoholics (n = 18). The results (mean and range) of this preliminary study show that alcoholics had significantly (p less than 0.0001) elevated plasma concentration of salsolinol sulfate (497; 50-1331 pg/ml) as compared to controls (93; 0-232 pg/ml). This was accompanied by significant (p less than 0.0003) elevation in plasma levels of dopamine sulfate. Elevation of plasma salsolinol sulfate reported here may be interpreted as a reflection of abnormalities in oxidative metabolism of dopamine, metabolically derived acetaldehyde, and/or biological carbonyls in chronic alcoholics.