Skip to main content
Advertisement

Main menu

  • Home
  • Articles
    • Current Issue
    • Fast Forward
    • Latest Articles
    • Special Sections
    • Archive
  • Information
    • Instructions to Authors
    • Submit a Manuscript
    • FAQs
    • For Subscribers
    • Terms & Conditions of Use
    • Permissions
  • Editorial Board
  • Alerts
    • Alerts
    • RSS Feeds
  • Virtual Issues
  • Feedback
  • Submit
  • Other Publications
    • Drug Metabolism and Disposition
    • Journal of Pharmacology and Experimental Therapeutics
    • Molecular Pharmacology
    • Pharmacological Reviews
    • Pharmacology Research & Perspectives
    • ASPET

User menu

  • My alerts
  • Log in
  • My Cart

Search

  • Advanced search
Molecular Pharmacology
  • Other Publications
    • Drug Metabolism and Disposition
    • Journal of Pharmacology and Experimental Therapeutics
    • Molecular Pharmacology
    • Pharmacological Reviews
    • Pharmacology Research & Perspectives
    • ASPET
  • My alerts
  • Log in
  • My Cart
Molecular Pharmacology

Advanced Search

  • Home
  • Articles
    • Current Issue
    • Fast Forward
    • Latest Articles
    • Special Sections
    • Archive
  • Information
    • Instructions to Authors
    • Submit a Manuscript
    • FAQs
    • For Subscribers
    • Terms & Conditions of Use
    • Permissions
  • Editorial Board
  • Alerts
    • Alerts
    • RSS Feeds
  • Virtual Issues
  • Feedback
  • Submit
  • Visit molpharm on Facebook
  • Follow molpharm on Twitter
  • Follow molpharm on LinkedIn
Abstract

Phenoxybenzamine treatment differentiates dopaminergic 3H-ligand binding sites in bovine caudate membranes.

M W Hamblin and I Creese
Molecular Pharmacology January 1982, 21 (1) 44-51;
M W Hamblin
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
I Creese
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Info & Metrics
  • eLetters
  • PDF
Loading

Abstract

Phenoxybenzamine, the classic alpha-adrenergic receptor alkylating agent, also acts as an irreversible antagonist of the binding of [3H]spiroperidol, a D-2-selective dopaminergic ligand, to bovine caudate membranes. Doses completely eliminating the binding of this ligand leave the binding of [3H]dopamine to D-3 sites virtually unaffected. The binding sites for these two ligands thus represent distinct subtypes of dopamine receptors, not interconverting states of a single receptor. This phenoxybenzamine-mediated inhibition proceeds via a dose-dependent (pseudo-IC50 = 1 microM) decrease in Bmax with little or no change in affinity for 3H-ligands at the D-2 site. The effect is site-directed, as the dopaminergic agonists dopamine and apomorphine and the antagonist domperidone are able to protect against phenoxybenzamine-mediated attack in proportion to their affinities for D-2 sites. Epinephrine, norepinephrine, and serotonin are much less effective in protecting these sites. The sensitivity of [3H]apomorphine binding is intermediate to that of [3H]spiroperidol and [3H]dopamine. [3H]Apomorphine binding can be resolved into a phenoxybenzamine-labile population of binding sites which have equal phenoxybenzamine sensitivity, selectivity among protecting agents, and butyrophenone affinity to those of D-2 sites labeled by 3H-butyrophenones, and a separate phenoxybenzamine-stable population of sites which have an affinity for dopamine comparable to that of D-3 sites labeled by [3H]dopamine. [3H]Apomorphine therefore appears to label a portion of D-2 receptor sites in addition to D-3 receptors.

MolPharm articles become freely available 12 months after publication, and remain freely available for 5 years. 

Non-open access articles that fall outside this five year window are available only to institutional subscribers and current ASPET members, or through the article purchase feature at the bottom of the page. 

 

  • Click here for information on institutional subscriptions.
  • Click here for information on individual ASPET membership.

 

Log in using your username and password

Forgot your user name or password?

Purchase access

You may purchase access to this article. This will require you to create an account if you don't already have one.
PreviousNext
Back to top

In this issue

Molecular Pharmacology
Vol. 21, Issue 1
1 Jan 1982
  • Table of Contents
  • Table of Contents (PDF)
  • Index by author
  • Back Matter (PDF)
  • Editorial Board (PDF)
  • Front Matter (PDF)
Download PDF
Article Alerts
Sign In to Email Alerts with your Email Address
Email Article

Thank you for sharing this Molecular Pharmacology article.

NOTE: We request your email address only to inform the recipient that it was you who recommended this article, and that it is not junk mail. We do not retain these email addresses.

Enter multiple addresses on separate lines or separate them with commas.
Phenoxybenzamine treatment differentiates dopaminergic 3H-ligand binding sites in bovine caudate membranes.
(Your Name) has forwarded a page to you from Molecular Pharmacology
(Your Name) thought you would be interested in this article in Molecular Pharmacology.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Abstract

Phenoxybenzamine treatment differentiates dopaminergic 3H-ligand binding sites in bovine caudate membranes.

M W Hamblin and I Creese
Molecular Pharmacology January 1, 1982, 21 (1) 44-51;

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero

Share
Abstract

Phenoxybenzamine treatment differentiates dopaminergic 3H-ligand binding sites in bovine caudate membranes.

M W Hamblin and I Creese
Molecular Pharmacology January 1, 1982, 21 (1) 44-51;
Reddit logo Twitter logo Facebook logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Google Plus One

Jump to section

  • Article
  • Info & Metrics
  • eLetters
  • PDF

Related Articles

Cited By...

Similar Articles

Advertisement
  • Home
  • Alerts
Facebook   Twitter   LinkedIn   RSS

Navigate

  • Current Issue
  • Fast Forward by date
  • Fast Forward by section
  • Latest Articles
  • Archive
  • Search for Articles
  • Feedback
  • ASPET

More Information

  • About Molecular Pharmacology
  • Editorial Board
  • Instructions to Authors
  • Submit a Manuscript
  • Customized Alerts
  • RSS Feeds
  • Subscriptions
  • Permissions
  • Terms & Conditions of Use

ASPET's Other Journals

  • Drug Metabolism and Disposition
  • Journal of Pharmacology and Experimental Therapeutics
  • Pharmacological Reviews
  • Pharmacology Research & Perspectives
ISSN 1521-0111 (Online)

Copyright © 2023 by the American Society for Pharmacology and Experimental Therapeutics