Agmatine ((4-aminobutyl)guanidine, NH2-CH2-CH2-CH2-CH2-NH-C(-NH2)(=NH)) is the decarboxylation product of the amino acid arginine and is an intermediate in polyamine biosynthesis. It is a putative neurotransmitter. It is synthesized in the brain, stored in synaptic vesicles, accumulated by uptake, released by membrane depolarization, and inactivated by agmatinase. Agmatine binds to 2-adrenergic receptor and imidazoline binding sites, and blocks NMDA receptors and other cation ligand-gated channels. Agmatine inhibits nitric oxide synthase (NOS), and induces the release of some peptide hormones. Treatment with exogenous agmatine exerts neuroprotective effects in animal models of neurotrauma.
Belongs to the class of organic compounds known as guanidines. Guanidines are compounds containing a guanidine moiety, with the general structure (R1R2N)(R3R4N)C=N-R5.
