Motilin receptors (provisional nomenclature, [6]) are activated by a 22 amino-acid peptide derived from a precursor (MLN, P12872), which may also generate a motilin-associated peptide (MLN, P12872). These receptors are also suggested to be responsible for the gastrointestinal prokinetic effects of certain macrolide antibiotics (often called motilides; e.g. erythromycin), although for many of these molecules the evidence is sparse.

In laboratory rodents, the gene encoding the motilin percursor appears to be absent, while the receptor appears to be a pseudogene. Functions of motilin (MLN, P12872) are not usually detected in rodents, although brain and other responses to motilin (MLN, P12872) and the macrolide ABT-229 have been reported and the mechanism of these actions are obscure [13-14].

* Key recommended reading is highlighted with an asterisk

* De Smet B, Mitselos A, Depoortere I. (2009) Motilin and ghrelin as prokinetic drug targets. Pharmacol. Ther., 123 (2): 207-23. [PMID:19427331]

* Foord SM, Bonner TI, Neubig RR, Rosser EM, Pin JP, Davenport AP, Spedding M, Harmar AJ. (2005) International Union of Pharmacology. XLVI. G protein-coupled receptor list. Pharmacol Rev, 57: 279-288. [PMID:15914470]

Sanger GJ. (2008) Motilin, ghrelin and related neuropeptides as targets for the treatment of GI diseases. Drug Discov. Today, 13 (5-6): 234-9. [PMID:18342799]

* Sanger GJ, Wang Y, Hobson A, Broad J. (2012) Motilin: Toward a new understanding of the gastrointestinal neuropharmacology and therapeutic use of motilin receptor agonists. Br. J. Pharmacol.,  [Epub ahead of print]. [PMID:23189978]

* Takeshita E, Matsuura B, Dong M, Miller LJ, Matsui H, Onji M. (2006) Molecular characterization and distribution of motilin family receptors in the human gastrointestinal tract. J Gastroenterol, 41: 223-230. [PMID:16699856]

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10. Matsuura B, Dong M, Coulie B, Pinon DI, Miller LJ. (2005) Demonstration of a specific site of covalent labeling of the human motilin receptor using a biologically active photolabile motilin analog. J Pharmacol Exp Ther, 313: 1101-1108. [PMID:15677347]

11. Matsuura B, Dong M, Miller LJ. (2002) Differential determinants for peptide and non-peptidyl ligand binding to the motilin receptor. Critical role of second extracellular loop for peptide binding and action. J Biol Chem, 277: 9834-9839. [PMID:11781320]

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