text: Agmatine was found to exert modulatory actions directly and indirectly at multiple key molecular targets underlying cellular control mechanisms of cardinal importance in health and disease. It is considered capable of exerting its modulatory actions simultaneously at multiple targets. The following outline indicates the categories of control mechanisms and identifies their molecular targets: 
  * Neurotransmitter receptors and receptor ionophores. Nicotinic, imidazoline I1 and I2, α2-adrenergic, glutamate NMDAr, and serotonin 5-HT2A and 5HT-3 receptors.
  * Ion channels. Including: ATP-sensitive K+ channels, voltage-gated Ca channels, and acid-sensing ion channels (ASICs).
  * Membrane transporters. Agmatine specific-selective uptake sites, organic cation transporters (mostly OCT2 subtype), extraneuronal monoamine transporters (ENT), polyamine transporters, and mitochondrial agmatine specific-selective transport system.
  * Nitric oxide (NO) synthesis modulation. Both differential inhibition and activation of NO synthase (NOS) isoforms is reported.
  * Polyamine metabolism. Agmatine is a precursor for polyamine synthesis, competitive inhibitor of polyamine transport, inducer of spermidine/spermine acetyltransferase (SSAT), and inducer of antizyme.
  * Protein ADP-ribosylation. Inhibition of protein arginine ADP-ribosylation.
  * Matrix metalloproteases (MMPs). Indirect down-regulation of the enzymes MMP 2 and 9.
  * Advanced glycation end product (AGE) formation. Direct blockade of AGEs formation.
  * NADPH oxidase. Activation of the enzyme leading to HO production.