Acetyl-L-CarnitineResearch on this acetylated derivative of L carnitine has centered largely on its role in maintaining brain and nerve function during aging. The acetyl group can serve as a metabolic source of acetylcholine, a brain neurotransmitter, while the L carnitine component carries fatty acids into mitochondria of nerve, heart, and muscle cells for use in energy production. Other actions benefit membrane stability, production of nerve growth factor, and