Comparison of the effects of verapamil and nifedipine on airway muscarinic reactivity and receptors

J. B. Cheng, Againdra K. Bewtra, R. G. Townley

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Previous studies have shown inconsistent results of the effect of verapamil and nifedipine on airway reactivity. This study was undertaken to determine and compare their effects on the activity of airway muscarinic receptors by contraction experiments and by radioligand receptor binding assays. We found that verapamil (10-5-10-4 M) reduced contraction at rat tracheal muscle to methacholine, a finding consistent with its inhibition on binding of (3H)QNB to bovine tracheal muscle membranes. Unlike verapamil, nifedipine (10-5-3 x 10-5 M) inhibited neither methacholine response nor (3H)QNB binding. Verapamil but not nifedipine decreased the affinity of binding sites. Neither of them affected the concentration of (3H)QNB binding sites. We conclude that the effect of verapamil on airway muscarinic receptor binding sites differs qualitatively from that of nifedipine, and suggest that its effect on the binding sites could account for the inhibitory action of verapamil on airway muscarinic response.

Original languageEnglish
Pages (from-to)47-61
Number of pages15
JournalArchives Internationales de Pharmacodynamie et de Therapie
Volume273
Issue number1
StatePublished - 1985
Externally publishedYes

Fingerprint

Muscarinic Receptors
Nifedipine
Verapamil
Binding Sites
Methacholine Chloride
Muscles
Cholinergic Agents
Membranes

All Science Journal Classification (ASJC) codes

  • Pharmacology

Cite this

Comparison of the effects of verapamil and nifedipine on airway muscarinic reactivity and receptors. / Cheng, J. B.; Bewtra, Againdra K.; Townley, R. G.

In: Archives Internationales de Pharmacodynamie et de Therapie, Vol. 273, No. 1, 1985, p. 47-61.

Research output: Contribution to journalArticle

@article{a82b9defc2344e00a1e68bc53b8059ea,
title = "Comparison of the effects of verapamil and nifedipine on airway muscarinic reactivity and receptors",
abstract = "Previous studies have shown inconsistent results of the effect of verapamil and nifedipine on airway reactivity. This study was undertaken to determine and compare their effects on the activity of airway muscarinic receptors by contraction experiments and by radioligand receptor binding assays. We found that verapamil (10-5-10-4 M) reduced contraction at rat tracheal muscle to methacholine, a finding consistent with its inhibition on binding of (3H)QNB to bovine tracheal muscle membranes. Unlike verapamil, nifedipine (10-5-3 x 10-5 M) inhibited neither methacholine response nor (3H)QNB binding. Verapamil but not nifedipine decreased the affinity of binding sites. Neither of them affected the concentration of (3H)QNB binding sites. We conclude that the effect of verapamil on airway muscarinic receptor binding sites differs qualitatively from that of nifedipine, and suggest that its effect on the binding sites could account for the inhibitory action of verapamil on airway muscarinic response.",
author = "Cheng, {J. B.} and Bewtra, {Againdra K.} and Townley, {R. G.}",
year = "1985",
language = "English",
volume = "273",
pages = "47--61",
journal = "Archives Internationales de Pharmacodynamie et de Therapie",
issn = "0003-9780",
publisher = "Wiley-Blackwell",
number = "1",

}

TY - JOUR

T1 - Comparison of the effects of verapamil and nifedipine on airway muscarinic reactivity and receptors

AU - Cheng, J. B.

AU - Bewtra, Againdra K.

AU - Townley, R. G.

PY - 1985

Y1 - 1985

N2 - Previous studies have shown inconsistent results of the effect of verapamil and nifedipine on airway reactivity. This study was undertaken to determine and compare their effects on the activity of airway muscarinic receptors by contraction experiments and by radioligand receptor binding assays. We found that verapamil (10-5-10-4 M) reduced contraction at rat tracheal muscle to methacholine, a finding consistent with its inhibition on binding of (3H)QNB to bovine tracheal muscle membranes. Unlike verapamil, nifedipine (10-5-3 x 10-5 M) inhibited neither methacholine response nor (3H)QNB binding. Verapamil but not nifedipine decreased the affinity of binding sites. Neither of them affected the concentration of (3H)QNB binding sites. We conclude that the effect of verapamil on airway muscarinic receptor binding sites differs qualitatively from that of nifedipine, and suggest that its effect on the binding sites could account for the inhibitory action of verapamil on airway muscarinic response.

AB - Previous studies have shown inconsistent results of the effect of verapamil and nifedipine on airway reactivity. This study was undertaken to determine and compare their effects on the activity of airway muscarinic receptors by contraction experiments and by radioligand receptor binding assays. We found that verapamil (10-5-10-4 M) reduced contraction at rat tracheal muscle to methacholine, a finding consistent with its inhibition on binding of (3H)QNB to bovine tracheal muscle membranes. Unlike verapamil, nifedipine (10-5-3 x 10-5 M) inhibited neither methacholine response nor (3H)QNB binding. Verapamil but not nifedipine decreased the affinity of binding sites. Neither of them affected the concentration of (3H)QNB binding sites. We conclude that the effect of verapamil on airway muscarinic receptor binding sites differs qualitatively from that of nifedipine, and suggest that its effect on the binding sites could account for the inhibitory action of verapamil on airway muscarinic response.

UR - http://www.scopus.com/inward/record.url?scp=0021907399&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0021907399&partnerID=8YFLogxK

M3 - Article

C2 - 3890784

AN - SCOPUS:0021907399

VL - 273

SP - 47

EP - 61

JO - Archives Internationales de Pharmacodynamie et de Therapie

JF - Archives Internationales de Pharmacodynamie et de Therapie

SN - 0003-9780

IS - 1

ER -