Glucagon-like peptide-1(7-36)amide: characterization of the domain responsible for binding to its receptor on rat insulinoma RINm5F cells.

Abstract

Glucagon-like peptide-1(7-36)amide (GLP-1(7-36)amide) is a potent stimulator of insulin secretion. Receptors for this hormone have been found on different insulinoma-derived cell lines, e.g. the RINm5F cell line which is derived from a radiation-induced rat insulinoma. To characterize the part of the GLP-1(7-36)amide molecule that is responsible for binding to its receptor on RINm5F cells, binding studies with synthetic C-terminal (GLP-1(21-36)amide) and synthetic N-terminal (GLP-1(7-25] GLP-1 fragments were carried out. GLP-1(21-36)amide showed dose-dependent binding to the GLP-1(7-36)amide receptor but was approximately 1500 times less potent in inhibiting binding of 125I-labelled GLP-1(7-36)amide than the intact hormone. GLP-1(7-25) at concentrations up to 10 mumol/l did not inhibit binding of label. Neither fragment changed intracellular cyclic AMP concentrations, in contrast to GLP-1(7-36)amide which increased intracellular cyclic AMP. GLP-1(21-36)amide, however, acted as a weak partial antagonist of GLP-1(7-36)amide with respect to GLP-1(7-36)amide-dependent stimulation of cyclic AMP production.

• Authors: B Gallwitz, W E Schmidt, J M Conlon, W Creutzfeldt
• Journal: Journal of molecular endocrinology (J Mol Endocrinol) Vol. 5 Issue 1 Pg. 33-9 (Aug 1990) ISSN: 0952-5041 [Print] England
• PMID: 2168708 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Glp1r protein, rat
• Glucagon-Like Peptide-1 Receptor
• Peptide Fragments
• Peptides
• Receptors, Cell Surface
• Receptors, Glucagon
• Glucagon-Like Peptides
• Glucagon-Like Peptide 1
• Glucagon
• glucagon-like peptide 1 (1-36)amide
• Cyclic AMP

Topics

• Animals
• Binding Sites
• Cyclic AMP (metabolism)
• Glucagon
• Glucagon-Like Peptide 1
• Glucagon-Like Peptide-1 Receptor
• Glucagon-Like Peptides
• Peptide Fragments (chemical synthesis, metabolism)
• Peptides (metabolism)
• Rats
• Receptors, Cell Surface (metabolism)
• Receptors, Glucagon
• Tumor Cells, Cultured