[Met5]-Enkephalin, amide is an agonist for δ opioid receptors as well as putative ζ (zeta) opioid receptors.Met-enkephalin circulates in several forms, some of which may be derived from proteins other than proenkephalin A, and plasma levels of both free native, and peptidase-derivable Met-enkephalin are modulated physiologically.

Ciproxifan 是一种高效且特异性的组胺 H3 受体拮抗剂 (IC50: 9.2 nM)。

甘氨酰肌氨酸是通过甘氨酸的羧基与肌氨酸的氨基进行形式缩合而获得的二肽。