[The receptor of calcitonin gene-related peptide (CGRP) is present on the membranes of insulinoma].
We demonstrate here that membranes prepared from beta cells which release insulin contain specific binding sites for calcitonin gene-related peptide (CGRP). The binding of 125I(His) human CGRP to beta cell membranes was protein concentration, time, temperature and pH dependent. Scatchard analysis of the data revealed a single class of binding sites with an apparent dissociation constant (Kd) of 1.5 nM and a maximal binding capacity of 19 fmol/mg of protein. Chicken CGRP inhibited the label binding whereas salmon calcitonin had only a weak effect. These results suggest that the effect of CGRP on insulin secretion is due to a direct action on beta cells.
Barakat
A
A
Unité I.N.S.E.R.M. U. n. 55, Hôpital Saint-Antoine, Paris.
Marie
J C
JC
Rosselin
G
G
D007516:Adenoma, Islet Cell / Q000648:ultrastructure*; D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism; D002462:Cell Membrane / Q000032:analysis; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007340:Insulinoma / Q000648:ultrastructure*; D010190:Pancreatic Neoplasms / Q000648:ultrastructure*; D018003:Receptors, Calcitonin; D011956:Receptors, Cell Surface / Q000032:analysis*; D013696:Temperature; D013997:Time Factors
D018003:Receptors, Calcitonin; D011956:Receptors, Cell Surface; D015740:Calcitonin Gene-Related Peptide
Le récepteur du peptide apparenté au gène de la calcitonine (CGRP) est présent sur les membranes des insulinomes.