Catalog Number: 5272
Alternate Names: Ibutamoren mesylate, L-163,191
Chemical Name: 2-Amino-N-[(1R)-2-[1,2-dihydro-1-(methylsulfonyl)spiro[3H-indole-3,4'-piperidin]-1'-yl]-2-oxo-1-[(phenylmethoxy)methyl]ethyl]-2-methylpropanamide methanesulfonate
Biological Activity
High affinity ghrelin receptor agonist (pKi = 8.14). Growth hormone (GH) secretagog; stimulates GH release from rat pituitary cells in vitro (EC50 = 1.3 nM) and enhances GH plasma levels in vivo. Also attenuates isoproterenol-induced lipolysis in rat adipocytes in vitro. Orally bioavailable.
Technical Data
  • M.Wt:
  • Formula:
  • Solubility:
    Soluble to 50 mM in water and to 100 mM in DMSO
  • Purity:
  • Storage:
    Store at +4°C
  • CAS No:
The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis. All Tocris products are intended for laboratory research use only.
Background References
  1. Growth hormone secretagogues and growth hormone releasing peptides act as orthosteric super-agonists but not allosteric regulators for activation of the G protein Galpha(o1) by the Ghrelin receptor.
    Bennett et al.
    Mol.Pharmacol., 2009;76:802
  2. Design and biological activities of L-163,191 (MK-0677): a potent, orally active growth hormone secretagogue.
    Patchett et al.
    Proc.Natl.Acad.Sci.U.S.A., 1995;92:7001
  3. Ghrelin and des-acyl ghrelin both inhibit isoproterenol-induced lipolysis in rat adipocytes via a non-type 1a growth hormone secretagogue receptor.
    Mucciolo et al.
    Eur.J.Pharmacol., 2004;498:27
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