ACTH (1-17) is a peptide fragment of adrenocorticotropic hormone , a peptide hormone found in the brain that is involved in the biological stress response.1 It binds to melanocortin receptors (MCRs; Kis = 0.23, 14, 419, and 4,240 nM for MC1R, MC3R, MC4R, and MC5R, respectively).2 It is an agonist at MC1R, increasing adenylate cyclase activity with an EC50 value of 3.02 nM in HEK293 cells expressing MC1R.3 ACTH (1-17) (160 μg/kg, i.v.) increases mean arterial blood pressure (MAP) following bleeding-induced hypotension in a rat model of hemorrhagic shock 15-30 minutes after administration.4 It induces melanogenesis in a biphasic manner (EC50s = 0.0001 and 0.08 nM) and differentiation of melanocytes when used at concentrations ranging from 0.01 to 1,000 nM.3,5
References
1. Strand, F.L., Lee, S.J., Zuccarelli, L.A., et al. Non-corticotropic ACTH peptides modulate nerve development and regeneration. Rev. Neurosci. 4(4), 321-363 (1993).
2. Schi•th, H.B., Muceniece, R., Larsson, M., et al. The melanocortin 1, 3, 4 or 5 receptors do not have a binding epitope for ACTH beyond the sequence of α-MSH. J. Endocrinol. 155(1), 73-78 (1997).
3. Tsatmalia, M., Wakamatsu, K., Graham, A.J., et al. Skin POMC peptides. Their binding affinities and activation of the human MC1 receptor. Ann. N.Y. Acad. Sci. 885(1), 466-469 (1999).
4. Bertolini, A., Guarini, S., Rompianesi, E., et al. α-MSH and other ACTH fragments improve cardiovascular function and survival in experimental hemorrhagic shock. Eur. J. Pharmacol. 130(1-2), 19-26 (1986).
5. Hirobe, T., and Hiroyuki, A. ACTH4-12 is the minimal message sequence required to induce the differentiation of mouse epidermal melanocytes in serum-free primary culture. J. Exp. Zool. 286(6), 632-640 (2000).