Recent studies have demonstrated that a natural chemical found in the brain, gamma-aminobutyric acid (GABA), which is also produced in large quantities by pancreatic beta-cells, has beta-cell regenerative and immunoregulatory effects. Importantly, GABA prevented and partially reversed diabetes in type 1 diabetes mouse models. It is important to address essential questions regarding the potential effects of GABA in diabetic patients in humans. Given the largely unknown mechanism of action of GABA in the pancreas, and the limited information on how GABA is absorbed, distributed and eliminated from the human body, we plan to examine these issues (referred to as pharmacokinetics/pharmacodynamics) in normal subjects.