Characterization of receptors for glucagon-like peptide-1(7-36)amide on rat lung membranes.
Specific binding of 125I-labelled GLP-1(7-36)amide to rat lung membranes was dependent upon time and temperature and was proportional to membrane protein concentration. Binding was inhibited in a concentration-dependent manner by unlabelled GLP-1(7-36)amide consistent with the presence of a single class of binding sites with a dissociation constant (Kd) of 1.67 +/- 0.29 nmol/l. GLP-1(1-36)amide was 260 times less potent in inhibiting the binding of 125I-labelled GLP-1(7-36)amide to lung membranes (Kd of 448 +/- 93 nmol/l). Vasoactive intestinal polypeptide and peptide-histidine-isoleucine also displaced 125I-labelled GLP-1(7-36)amide from the receptor concentration-dependently; the Kd was 4.31 +/- 0.8 and 7.93 +/- 4.79 nmol/l, respectively. Guanine nucleotides (GTP-gamma-S, GDP-beta-S) decreased the binding of 125I-labelled GLP-1(7-36)amide to rat lung membranes as was found for GLP-1(7-36)amide receptors in RINm5F cells which were also shown to be coupled to the adenylate cyclase system.
Richter
G
G
Department of Internal Medicine, Philipps-University of Marburg, FRG.
Göke
R
R
Göke
B
B
Arnold
R
R
D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D002462:Cell Membrane / Q000201:enzymology / Q000378:metabolism; D005934:Glucagon; D052216:Glucagon-Like Peptide 1; D000067757:Glucagon-Like Peptide-1 Receptor; D004763:Glucagon-Like Peptides; D007700:Kinetics; D008168:Lung / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D010446:Peptide Fragments; D010455:Peptides / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000378:metabolism; D018027:Receptors, Glucagon
C000593835:Glp1r protein, rat; D000067757:Glucagon-Like Peptide-1 Receptor; D010446:Peptide Fragments; D010455:Peptides; D011956:Receptors, Cell Surface; D018027:Receptors, Glucagon; C055453:glucagon-like peptide 1 (7-36)amide; D004763:Glucagon-Like Peptides; D052216:Glucagon-Like Peptide 1; D005934:Glucagon; D000262:Adenylyl Cyclases