No is synthesized from:

Also called asEndothelium derived Relaxing Factor NO (nitric oxide): - synthesized fromArginineby enzymeNOS(Nitric oxide synthase) in the endothelial cells Nitric oxide relaxes the smooth muscles of blood vessels The vasodilator - nitroglycerin also enters smooth muscle cells, where its metabolism also leads to the formation of NO. There are three isoforms of NOS (Nitric oxide synthase) n NOS - neuronal i NOS- inducible e NOS- endothelial