Pituitary adenylate cyclase-activating polypeptide receptors of types I and II and glucagon-like peptide-I receptors are expressed in the rat medullary carcinoma of the thyroid cell line 6/23.
The expression of the messenger RNAs coding for glucagon-like peptide-I (GLP-I) receptor, VIP receptor, and pituitary adenylate cyclase-activating polypeptide (PACAP) receptor as well as the expression of the receptor proteins were demonstrated in the rat medullary carcinoma of thyroid cell line 6/23 by the following experiments: 1) RNA extraction, reverse transcriptase, and polymerase chain reaction with specific primers; 2) binding of the radiolabeled ligands [125I]GLP-I-(7-36)-NH2, [125I]PACAP-(1-27), and [125I]VIP and inhibition by, respectively, unlabeled GLP-I-(7-36)-NH2, PACAP-(1-27), and VIP; and 3) study of adenylate cyclase activation by the peptides and selective inhibition of the VIP/PACAP response by the antagonist [D-Phe2]VIP. Besides the highly selective GLP-I receptor, PACAP receptors of types I and II were present on the cell line and coupled to adenylate cyclase. PACAP stimulated the adenylate cyclase through type I and II receptors, whereas VIP interacted with type II receptors only. Messenger RNA analysis indicated that at least three splice variants of the PACAP type I receptor may be expressed in 6/23 cells.
Vertongen
P
P
Department of Biochemistry and Nutrition, Medical School, Université Libre de Bruxelles, Belgium.
Ciccarelli
E
E
Woussen-Colle
M C
MC
De Neef
P
P
Robberecht
P
P
Cauvin
A
A
D000262:Adenylyl Cyclases / Q000032:analysis; D000818:Animals; D001483:Base Sequence; D018276:Carcinoma, Medullary / Q000737:chemistry* / Q000235:genetics / Q000473:pathology*; D004273:DNA, Neoplasm / Q000032:analysis / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic; D000067757:Glucagon-Like Peptide-1 Receptor; D007457:Iodine Radioisotopes; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D051381:Rats; D011956:Receptors, Cell Surface / Q000032:analysis* / Q000235:genetics / Q000502:physiology; D018027:Receptors, Glucagon; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I; D011979:Receptors, Pituitary Hormone / Q000032:analysis* / Q000235:genetics / Q000502:physiology; D018005:Receptors, Vasoactive Intestinal Peptide / Q000032:analysis / Q000235:genetics / Q000502:physiology; D013964:Thyroid Neoplasms / Q000737:chemistry* / Q000235:genetics / Q000473:pathology*; D014407:Tumor Cells, Cultured
D004273:DNA, Neoplasm; C000593835:Glp1r protein, rat; D000067757:Glucagon-Like Peptide-1 Receptor; D007457:Iodine Radioisotopes; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D018027:Receptors, Glucagon; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I; D011979:Receptors, Pituitary Hormone; D018005:Receptors, Vasoactive Intestinal Peptide; D000262:Adenylyl Cyclases