Functional calcitonin gene-related peptide subtype 2 receptors in porcine coronary arteries are identified as calcitonin gene-related peptide subtype 1 receptors by radioligand binding and reverse transcription-polymerase chain reaction

Boyd R. Rorabaugh, Margaret A. Scofield, D. David Smith, William B. Jeffries, Peter W. Abel

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

Calcitonin gene-related peptide (CGRP) receptors are classified into CGRP subtype 1 (CGRP1) and CGRP subtype 2 (CGRP2) based on the affinity of the antagonist, human α (hα)-CGRP8-37. hα-CGRP8-37 antagonizes CGRP1 receptor-mediated responses with high affinity (KB <100 nM) and antagonizes CGRP2 receptor-mediated responses with low affinity (KB > 1 μM). CGRP2 receptors have been previously reported to mediate relaxation of large porcine coronary arteries because this action is antagonized with low affinity by hα-CGRP8-37. In the present study, we used reverse transcription-polymerase chain reaction, radioligand binding, and values from our previously reported isolated tissue experiments to compare the CGRP receptor in porcine coronary arteries with the porcine CGRP1 receptor stably expressed in human embryonic kidney (HEK) 293 cells. We identified calcitonin receptor-like receptor and receptor activity modifying protein 1 mRNA in coronary arteries. We also found that the ligand binding characteristics of the CGRP receptor in coronary arteries and the cloned CGRP1 receptor were highly similar. K1 values for hα-CGRP8-37 were 6.6 and 5.7 nM in porcine coronary arteries and the cloned CGRP1 receptor, respectively. The affinities (KB) of hα-CGRP8-37 and five other antagonists were 22- to 707-fold lower in functional experiments measuring relaxation of coronary arteries than in radioligand binding experiments. Despite this difference in absolute affinity values, there was a high correlation of the rank order of affinity for the antagonists determined by the two methods. Thus hα-CGRP8-37 antagonizes CGRP-induced relaxation of porcine coronary arteries with low affinity at the CGRP1 receptor. Taken together, these data do not support the existence of the CGRP2 receptor.

Original languageEnglish
Pages (from-to)1086-1094
Number of pages9
JournalJournal of Pharmacology and Experimental Therapeutics
Volume299
Issue number3
StatePublished - 2001

Fingerprint

Calcitonin Gene-Related Peptide
Reverse Transcription
Coronary Vessels
Swine
Polymerase Chain Reaction
Calcitonin Gene-Related Peptide Receptors
Receptor Activity-Modifying Protein 1
Calcitonin Receptor-Like Protein
calcitonin gene-related peptide (8-37)
Ligands
Kidney
Messenger RNA

All Science Journal Classification (ASJC) codes

  • Pharmacology

Cite this

@article{6aa3b09948804897af0ebdd7c9f219a1,
title = "Functional calcitonin gene-related peptide subtype 2 receptors in porcine coronary arteries are identified as calcitonin gene-related peptide subtype 1 receptors by radioligand binding and reverse transcription-polymerase chain reaction",
abstract = "Calcitonin gene-related peptide (CGRP) receptors are classified into CGRP subtype 1 (CGRP1) and CGRP subtype 2 (CGRP2) based on the affinity of the antagonist, human α (hα)-CGRP8-37. hα-CGRP8-37 antagonizes CGRP1 receptor-mediated responses with high affinity (KB <100 nM) and antagonizes CGRP2 receptor-mediated responses with low affinity (KB > 1 μM). CGRP2 receptors have been previously reported to mediate relaxation of large porcine coronary arteries because this action is antagonized with low affinity by hα-CGRP8-37. In the present study, we used reverse transcription-polymerase chain reaction, radioligand binding, and values from our previously reported isolated tissue experiments to compare the CGRP receptor in porcine coronary arteries with the porcine CGRP1 receptor stably expressed in human embryonic kidney (HEK) 293 cells. We identified calcitonin receptor-like receptor and receptor activity modifying protein 1 mRNA in coronary arteries. We also found that the ligand binding characteristics of the CGRP receptor in coronary arteries and the cloned CGRP1 receptor were highly similar. K1 values for hα-CGRP8-37 were 6.6 and 5.7 nM in porcine coronary arteries and the cloned CGRP1 receptor, respectively. The affinities (KB) of hα-CGRP8-37 and five other antagonists were 22- to 707-fold lower in functional experiments measuring relaxation of coronary arteries than in radioligand binding experiments. Despite this difference in absolute affinity values, there was a high correlation of the rank order of affinity for the antagonists determined by the two methods. Thus hα-CGRP8-37 antagonizes CGRP-induced relaxation of porcine coronary arteries with low affinity at the CGRP1 receptor. Taken together, these data do not support the existence of the CGRP2 receptor.",
author = "Rorabaugh, {Boyd R.} and Scofield, {Margaret A.} and Smith, {D. David} and Jeffries, {William B.} and Abel, {Peter W.}",
year = "2001",
language = "English",
volume = "299",
pages = "1086--1094",
journal = "Journal of Pharmacology and Experimental Therapeutics",
issn = "0022-3565",
publisher = "American Society for Pharmacology and Experimental Therapeutics",
number = "3",

}

TY - JOUR

T1 - Functional calcitonin gene-related peptide subtype 2 receptors in porcine coronary arteries are identified as calcitonin gene-related peptide subtype 1 receptors by radioligand binding and reverse transcription-polymerase chain reaction

AU - Rorabaugh, Boyd R.

AU - Scofield, Margaret A.

AU - Smith, D. David

AU - Jeffries, William B.

AU - Abel, Peter W.

PY - 2001

Y1 - 2001

N2 - Calcitonin gene-related peptide (CGRP) receptors are classified into CGRP subtype 1 (CGRP1) and CGRP subtype 2 (CGRP2) based on the affinity of the antagonist, human α (hα)-CGRP8-37. hα-CGRP8-37 antagonizes CGRP1 receptor-mediated responses with high affinity (KB <100 nM) and antagonizes CGRP2 receptor-mediated responses with low affinity (KB > 1 μM). CGRP2 receptors have been previously reported to mediate relaxation of large porcine coronary arteries because this action is antagonized with low affinity by hα-CGRP8-37. In the present study, we used reverse transcription-polymerase chain reaction, radioligand binding, and values from our previously reported isolated tissue experiments to compare the CGRP receptor in porcine coronary arteries with the porcine CGRP1 receptor stably expressed in human embryonic kidney (HEK) 293 cells. We identified calcitonin receptor-like receptor and receptor activity modifying protein 1 mRNA in coronary arteries. We also found that the ligand binding characteristics of the CGRP receptor in coronary arteries and the cloned CGRP1 receptor were highly similar. K1 values for hα-CGRP8-37 were 6.6 and 5.7 nM in porcine coronary arteries and the cloned CGRP1 receptor, respectively. The affinities (KB) of hα-CGRP8-37 and five other antagonists were 22- to 707-fold lower in functional experiments measuring relaxation of coronary arteries than in radioligand binding experiments. Despite this difference in absolute affinity values, there was a high correlation of the rank order of affinity for the antagonists determined by the two methods. Thus hα-CGRP8-37 antagonizes CGRP-induced relaxation of porcine coronary arteries with low affinity at the CGRP1 receptor. Taken together, these data do not support the existence of the CGRP2 receptor.

AB - Calcitonin gene-related peptide (CGRP) receptors are classified into CGRP subtype 1 (CGRP1) and CGRP subtype 2 (CGRP2) based on the affinity of the antagonist, human α (hα)-CGRP8-37. hα-CGRP8-37 antagonizes CGRP1 receptor-mediated responses with high affinity (KB <100 nM) and antagonizes CGRP2 receptor-mediated responses with low affinity (KB > 1 μM). CGRP2 receptors have been previously reported to mediate relaxation of large porcine coronary arteries because this action is antagonized with low affinity by hα-CGRP8-37. In the present study, we used reverse transcription-polymerase chain reaction, radioligand binding, and values from our previously reported isolated tissue experiments to compare the CGRP receptor in porcine coronary arteries with the porcine CGRP1 receptor stably expressed in human embryonic kidney (HEK) 293 cells. We identified calcitonin receptor-like receptor and receptor activity modifying protein 1 mRNA in coronary arteries. We also found that the ligand binding characteristics of the CGRP receptor in coronary arteries and the cloned CGRP1 receptor were highly similar. K1 values for hα-CGRP8-37 were 6.6 and 5.7 nM in porcine coronary arteries and the cloned CGRP1 receptor, respectively. The affinities (KB) of hα-CGRP8-37 and five other antagonists were 22- to 707-fold lower in functional experiments measuring relaxation of coronary arteries than in radioligand binding experiments. Despite this difference in absolute affinity values, there was a high correlation of the rank order of affinity for the antagonists determined by the two methods. Thus hα-CGRP8-37 antagonizes CGRP-induced relaxation of porcine coronary arteries with low affinity at the CGRP1 receptor. Taken together, these data do not support the existence of the CGRP2 receptor.

UR - http://www.scopus.com/inward/record.url?scp=0035192897&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0035192897&partnerID=8YFLogxK

M3 - Article

VL - 299

SP - 1086

EP - 1094

JO - Journal of Pharmacology and Experimental Therapeutics

JF - Journal of Pharmacology and Experimental Therapeutics

SN - 0022-3565

IS - 3

ER -