TY - JOUR
T1 - Glucagon-like peptide-1(7-36)amide
T2 - Characterization of the domain responsible for binding to its receptor on rat insulinoma RINm5F cells
AU - Gallwitz, B.
AU - Schmidt, W. E.
AU - Conlon, J. M.
AU - Creutzfeldt, W.
PY - 1990
Y1 - 1990
N2 - 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)amide at concentrations up to 10 μmol/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.
AB - 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)amide at concentrations up to 10 μmol/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.
UR - http://www.scopus.com/inward/record.url?scp=0025284895&partnerID=8YFLogxK
U2 - 10.1677/jme.0.0050033
DO - 10.1677/jme.0.0050033
M3 - Article
C2 - 2168708
AN - SCOPUS:0025284895
SN - 0952-5041
VL - 5
SP - 33
EP - 39
JO - Journal of Molecular Endocrinology
JF - Journal of Molecular Endocrinology
IS - 1
ER -