BAM-22P is an endogenous neuropeptide derived from proenkephalin A.1 It is expressed primarily in the adrenal medulla and at lower concentrations throughout the brain. BAM-22P binds µ-, κ-, and δ-opioid receptors (Kis = 0.9, 2.9, and 7.2 nM, respectively).2 Intracerebroventricular administration of BAM-22P induces analgesia in a tail-flick assay in mice (ED50 = 6.4 nM).1 It decreases the frequency of tail flicking, as well as paw lifting and licking in a rat model of formalin-induced nocifensive behavior when administered intrathecally at a dose of 5 nM/animal.3
1.HÖllt, V., Haarmann, I., Grimm, C., et al.Pro-enkephalin intermediates in bovine brain and adrenal medulla: Characterization of immunoreactive peptides related to BAM-22P and peptide FLife Sci.31(16-17)1883-1886(1982) 2.GarzÓn, J., SÁnchez-BlÁzquez, P., HÖllt, V., et al.Endogenous opioid peptides: Comparative evaluation of their receptor affinities in the mouse brainLife Sci.33(Suppl 1)291-294(1983) 3.Hong, Y., Dai, P., Jiang, J., et al.Dual effects of intrathecal BAM22 on nociceptive responses in acute and persistent pain—potential function of a novel receptorBr. J. Pharmacol.141(3)423-430(2004)