Novel vascular effects of isoprenaline following pacing-induced heart failure in the dog.

Published

Journal Article

Isoprenaline produced concentration-dependent contractions of the in vitro canine saphenous vein which were attenuated by phentolamine (10(-6) M) and pacing-induced heart failure. Both at control and peak heart failure, a biphasic response was seen in the dorsal pedal artery, consisting of an initial relaxation followed by a contraction; phentolamine and heart failure enhanced the relaxation component. In the presence of propranolol, the isoprenaline-induced contraction was sensitive to yohimbine, but resistant to prazosin. Therefore it is concluded that isoprenaline interacts not only with vascular beta-adrenoceptors, but also with alpha 2-adrenoceptors. Endothelial denudation resulted in a diminished response to isoprenaline in control saphenous vein and dorsal pedal artery but not in vessels from dogs with heart failure. The observation that the contractile response to isoprenaline diminishes in heart failure implies a specific down-regulation of peripheral vascular alpha 2-adrenoceptors.

Full Text

Duke Authors

Cited Authors

  • Forster, C; Wanes, D; Armstrong, PW

Published Date

  • August 6, 1991

Published In

Volume / Issue

  • 200 / 2-3

Start / End Page

  • 251 - 257

PubMed ID

  • 1664328

Pubmed Central ID

  • 1664328

International Standard Serial Number (ISSN)

  • 0014-2999

Digital Object Identifier (DOI)

  • 10.1016/0014-2999(91)90579-f

Language

  • eng

Conference Location

  • Netherlands