Determination of ( R)- and ( S)-Salsolinol sulfate and dopamine sulfate levels in plasma of nonalcoholics and alcoholics

Abstract

We have developed a new method to determine free as well as sulfoconjugated salsolinol (SAL), separated into both enantiomers, and free and sulfoconjugated dopamine in human blood plasma. Among the group of nonalcoholics ( R)-SAL (mean t SEM: 0.24 ± 0.07 ng/ml) was found in all blood samples and ( S)-SAL in 1 out of 20 (0.08 ng/ml). Ethanol loading induced a rise of both enantiomers as well as of dopamine whereby ( S)-SAL was detected in the plasma of 13 subjects only [( R)-SAL: 0.79 ± 0.24 ng/ml; ( S)-SAL: 0.49 ± 0.15 ng/ml; DA: 8.84 ± 0.75 ng/ml]. The later finding favors the notion of an enzymatic formation of ( S)-SAL. In alcoholics, ( R)-SAL and ( S)-SAL were elevated at the day of admission for detoxification [( R)-SAL: 0.65 ± 0.82 ng/ml; ( S)-SAL: 0.35 ± 0.05 ng/ml] and normalized after several months, suggesting intoxication marker characteristics [month 6: ( R)-SAL: 0.24 ± 0.14 ng/ml; ( S)-SAL: 0.20 t 0.05 ng/ml]. Patients with alcoholic parents had lowered. ( R)-SAL and ( S)-SAL levels compared with family history negative alcoholics, suggesting genetic association of disturbance of the SAL biosynthesis and alcoholism. Among the personality traits, suicidality was linked with low ( R)-SAL and ( S)-SAL concentrations in contrast to novelty seeking, impulsivity, and harm avoidance scores. The scores on the self-rating anxiety scale correlated positive with ( R)-SAL. These findings suggest trait marker characteristics of salsolinol.