PMID: 6108676Sep 1, 1980Paper

Competitive blockade of alpha-adrenergic receptors in rat heart by prazosin

Acta Pharmacologica Et Toxicologica
T SkomedalI Oye

Abstract

Phenylephrine (PE) in presence of propranolol evokes an alpha-adrenergic inotropic response in rat heart. The time course of this response is characterized by a transient decrease in maximal developed tension (Tmax) to subcontrol levels (negative phase of the inotropic response) followed by an increase which reaches maximum after 4-5 min. (positive phase of the inotropic response). Prazosin (PRZ), a selective alpha 1-receptor blocker, inhibited preferentially the positive phase of the inotropic response and displaced the dose-response curve of PE to the right in nanomolar concentrations, indicating a competitive mechanism of inhibition. Phentolamine, a non-selective alpha-blocker, blocked both the negative and the positive phase of the inotropic response to about the same degree. PRZ appears to be a competitive alpha-adrenergic antagonist with high affinity in rat heart. Two populations of alpha-adrenergic receptors may be present: one stimulatory (alpha 1) and one inhibitory.

References

Nov 3, 1975·Naunyn-Schmiedeberg's Archives of Pharmacology·K StarkeH D Taube
Jul 1, 1978·European Journal of Pharmacology·D C U'PrichardS H Snyder
Oct 1, 1979·British Journal of Pharmacology·G M Drew, S B Whiting
Oct 1, 1976·General Pharmacology·K Starke, T Endo
Dec 1, 1978·Proceedings of the National Academy of Sciences of the United States of America·P GuicheneyP Meyer
Sep 12, 1979·Biochemical and Biophysical Research Communications·J S KarlinerC T Dollery
Dec 1, 1979·Naunyn-Schmiedeberg's Archives of Pharmacology·P B TimmermansP A van Zwieten
May 1, 1973·British Journal of Pharmacology·B G Benfey
Jan 1, 1972·Naunyn-Schmiedeberg's Archives of Pharmacology·K Starke
Jul 1, 1974·Biochemical Pharmacology·S Z Langer
Nov 1, 1969·The American Journal of Physiology·A H HendersonE H Sonnenblick

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Citations

Jul 31, 1998·The American Journal of Physiology·G O AndersenJ B Osnes
Feb 1, 1983·Naunyn-Schmiedeberg's Archives of Pharmacology·M Gerold, G Haeusler
Dec 1, 1987·Naunyn-Schmiedeberg's Archives of Pharmacology·R G Chess-WilliamsD J Sheridan
Jul 1, 1983·Acta Pharmacologica Et Toxicologica·H AassJ B Osnes
Aug 1, 1982·Naunyn-Schmiedeberg's Archives of Pharmacology·S YamadaW R Roeske
Aug 1, 1986·Clinical and Experimental Pharmacology & Physiology·J VincentJ L Reid
Mar 1, 1987·Basic Research in Cardiology·A N Oksendal, P Jynge
May 22, 2004·Journal of Pharmacological Sciences·Maura FloreaniPaola Dorigo
Jun 15, 1984·Biochemical Pharmacology·T SkomedalJ B Osnes
Nov 26, 2003·European Journal of Pharmacology·Eirik QvigstadTor Skomedal

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