Glycine and Oral D-Cycloserine in Alcoholic Patients and Healthy Subjects

Question #1: Will glycine ameliorate cognitive deficits? Hypothesis #1: Based on positive findings conducted with glycine and milacemide, a glycine prodrug, in schizophrenia and dementia, we expect that glycine will ameliorate cognitive deficits. Question #2: Will alcoholic patients show enhanced endocrinal effects to glycine? Hypothesis #2: Based on the dose-related effects of glycine in healthy subjects, we expect that glycine will increase the endocrinal response to glycine in alcoholic patients with, supposedly, dysregulated NMDA receptor function. Question #3: Will D-cycloserine have ethanol-like effects? Hypothesis #3: If inhibition of NMDA receptor function is fundamental to the subjective effects of ethanol, then the NMDA antagonist properties of D-cycloserine should be recognized as ethanol-like (relative to placebo) in recently detoxified alcoholics and healthy subjects. Question #4: Will D-cycloserine reverse cognitive benefits of glycine? Hypothesis 4: Based on the dose related NMDA antagonist activity of D-cycloserine, we expect that D-cycloserine will compete with the agonist activity of glycine and therefore it will reverse the cognitive benefits of glycine. Question #5: Will D-cycloserine inhibit endocrinal effects of glycine? Hypothesis #5: If the agonist activity of glycine is necessary to determine endocrine response, then the dose-related NMDA antagonist properties of D-cycloserine should block these effects.