General and comparative endocrinology

Does motilin peptide regulate gastrointestinal motility of zebrafish? An in vitro study using isolated intestinal strips.

PMID 28242309


Motilin (MOT), a 22-amino-acid peptide hormone produced in the duodenal mucosa, stimulates gastrointestinal motility in mammals and birds, and it is a mediator of interdigestive motor complexes. Recently, expression of MOT-like peptide (MOTLP) and its receptor mRNAs was identified in zebrafish. The aim of the present study was to determine whether the zebrafish MOTLP (zfMOTLP, HIAFFSPKEMRELREKE) affects zebrafish gastrointestinal motility, with comparison to the effect of human MOT, in which five amino acids are identical to zfMOTLP at positions 5, 9, 15, 16, and 17. zfMOTLP caused small contractions of the rabbit duodenum and chicken ileum but, the sensitivity was about 3000-times lower than that of human MOT. zfMOTLP-induced contraction in the rabbit duodenum was decreased by pretreatment of the MOT receptor antagonist GM109, indicating that zfMOTLP could bind to the MOT receptor. zfMOTLP (3-100nM) increased the intracellular Ca