Peptide directoryGut, pancreas & liver

Neuromedin C

The last ten residues of GRP, as active as the whole.

Where it comes from

Made in
Cut from GRP in gut and brain
Sent out by
With GRP
Acts on
  • G cells
  • Gut smooth muscle
  • Pancreas

What it does

  • Everything GRP does, through the same receptor and at much the same potency: the receptor reads only the amidated tail 1
  • The decapeptide that frog bombesin shares, which is why a peptide from a European toad predicted a human hormone
  • In rat brain it is found alongside neuromedin B in the same regions, in a fixed ratio to full-length GRP 1

In medicine

  • None of its own: GRP assays count it with the parent peptide, and no clinical test separates them
  • Pro-GRP, the tumour marker used in small-cell lung cancer, comes from the other end of the precursor and says nothing about how much of this fragment is present

Beyond the body’s own use

  • Not studied apart from GRP, and no analogue of it has been taken into a person
  • Its interest is in what it rules out. Since ten residues carry the full activity, the longer sequence must be doing something else, or nothing, and the itch and tumour work has been done with whichever form was easier to make 2

Sources

  1. Minamino et al., Neuromedin B and neuromedin C, two mammalian bombesin-like peptides, Annals of the New York Academy of Sciences 1988
  2. Sun & Chen, A gastrin-releasing peptide receptor mediates the itch sensation in the spinal cord, Nature 2007

This card describes what a medicine is for and what the evidence says; it recommends nothing. Talk to your clinician about anything you read here.