Member of the B-vitamin family, is an essential nutrient in human nutrition. Pantothenic acid is involved in a number of biological reactions, including the production of energy, the catabolism of fatty acids and amino acids, the synthesis of fatty acids, phospholipids, sphingolipids, cholesterol and steroid hormones, and the synthesis of heme and the neurotransmitter acetylcholine. It also appears to be involved in the regulation of gene expression and in signal transduction.