Erythromycin and its derivatives with motilin-like biological activities inhibit the specific binding of 125I-motilin to duodenal muscle

Biochem Biophys Res Commun. 1988 Jan 29;150(2):877-82. doi: 10.1016/0006-291x(88)90474-3.


Erythromycin, one of the macrolide antibiotics, and its derivatives had been found to mimic actions of exogenous motilin, a gastrointestinal peptide hormone. We found that some of the macrolide compounds inhibited the specific binding of 125I-motilin to rabbit duodenum muscle at 15 C in a dose-dependent fashion. The inhibitory activity of several macrolides examined did not relate to their antibacterial activity but to their motilin-like activity. A 50% inhibition by EM536, a non-antibacterial erythromycin derivative with the highest motilin-like activity, was obtained at 3-40 nM and little higher than that of non-radioactive motilin (5-6 nM) under the present conditions. The results suggest that erythromycin and its derivatives mimic physiological actions of motilin by acting as agonists for a motilin receptor.

MeSH terms

  • Animals
  • Duodenum / metabolism
  • Erythromycin / analogs & derivatives*
  • Erythromycin / pharmacology*
  • In Vitro Techniques
  • Kinetics
  • Motilin / metabolism
  • Motilin / physiology*
  • Muscle, Smooth / metabolism
  • Rabbits
  • Receptors, Gastrointestinal Hormone / drug effects
  • Receptors, Gastrointestinal Hormone / metabolism*
  • Receptors, Neuropeptide*
  • Structure-Activity Relationship


  • Receptors, Gastrointestinal Hormone
  • Receptors, Neuropeptide
  • motilin receptor
  • Motilin
  • Erythromycin