THE EFFECT OF COCAINE ABUSE ON PLASMA-LEVELS OF SULFATED DOPAMINE ANDSALSOLINOL IN ALCOHOLICS

This study investigated the effect of cocaine abuse on peripheral dopa mine and its tetrahydroisoquinoline metabolite salsolinol in chronic a lcoholics. Specifically, the concentration of dopamine sulfate and sal solinol sulfate was measured in plasma samples obtained from the blood of a group of alcoholics (n = 40) and alcoholics with cocaine depende nce (n = 55). The concentrations of sulfoconjugated dopamine and salso linol were measured by a radioenzymatic technique. The results of this study showed that chronic alcoholics (627 +/- 195 pg/ml) and alcoholi cs with cocaine addiction (409 +/- 76 pg/ml) had significantly (p < 0. 05) elevated levels of salsolinol sulfate (mean +/- SEM) in their plas ma as compared to controls (99.5 +/- 7.5 pg/ml). However, alcoholics w ith cocaine dependence produced significantly (p < 0.01) higher concen tration of dopamine sulfate in their plasma (7520 +/- 1299 pg/ml) as c ompared to chronic alcoholics (3896 +/- 438 pg/ml) and controls (2124 +/- 104 pg/ml). Differences in plasma dopamine sulfate among alcoholic s with cocaine dependence vs. alcoholics without cocaine dependence ma y be interpreted as a reflection of increased extracellular dopamine m etabolism associated with chronic cocaine exposure.