Objective: The importance of serum levels of amino-acid neurotransmitters and of relevant enzymes has not been adequately evaluated in alcoholics. It is hypothesized that several of these neurotransmitters would be likely to be elevated in alcoholics overall, those with alcoholic withdrawal and, especially, individuals undergoing severe withdrawal as might be seen in delirium tremens (DTs).
Method: The subjects for these evaluations (N = 106 men) were 46 hospitalized patients with DTs, 20 subjects with an alcohol withdrawal syndrome (AWS) in the absence of DTs, 20 alcohol-dependent individuals not demonstrating withdrawal (ADS) and 20 nonalcoholic controls. The analyses evaluated the serum levels of glutamate (Glu), aspartate (Asp), gamma-aminobutyric acid (GABA) and glycine (Gly), as well as the activity of the relevant enzymes glutamic acid decarboxylase (GAD) and GABA transaminase (GABA-T).
Results: In these analyses, the subjects with DTs had significantly lower serum values for Gly and GAD, as well as for GABA, while demonstrating elevated values for Asp and Glu.
Conclusions: These data support the possibility that some of the symptoms of alcohol withdrawal, especially DTs, may be related to an altered balance between neurotoxic, or excitatory, and inhibitory amino-acid neurotransmitters.