Histamine, an organic nitrogen compound, works on target cells in the mammalian brain by stimulating of Histamine 1/2.

M-2420 is a fluorogenic substrate containing β-secretase site of the Swedish mutation of amyloid precursor protein (APP).

Exendin-3 is a biologically active peptides isolated from venoms of the Gila monster lizards, Heloderma horridurn . Exendin-3 is a pancreatic secretagogue, which is a member of the glucagon family. It is found in the venom of Heloderma horridurn, which is a Gila monster lizard.