umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Effects of alpha 2-adrenoceptor blockade and thyrotropin-releasing hormone (TRH) on the cardiovascular system in the rabbit.
Department of Physiology and Medical Biophysics, Biomedical Centre, Uppsala University, Uppsala, Sweden.
1991 (English)In: Acta Physiologica Scandinavica, ISSN 0001-6772, E-ISSN 1365-201X, Vol. 143, no 2, p. 187-194Article in journal (Refereed) Published
Abstract [en]

The effects of two different doses of thyrotropin-releasing hormone on regional blood flows were studied in urethane-anaesthetized rabbits pretreated with the alpha 2-adrenergic antagonists yohimbine and idazoxan. The effects of yohimbine were also studied using unanaesthetized rabbits. Blood flow measurements were performed using the tracer microsphere method. Thyrotropin-releasing hormone was injected i.v. at a dose of either 0.1 mg kg-1 or 2.0 mg kg-1. Yohimbine and idazoxan did not modify the effect of thyrotropin-releasing hormone on mean arterial blood pressure. In the anaesthetized animals, blockade of the alpha 2-adrenoceptors resulted in a vasoconstriction in several peripheral organs and the vasoconstriction increased after thyrotropin-releasing hormone administration. Pretreament with yohimbine reduced total cerebral blood flow moderately and in such animals thyrotropin-releasing hormone elicited only minor cerebral blood flow effects. Pretreatment with idazoxan did not reduce the total cerebral blood flow and in such animals it increased from 53 +/- 1 to 75 +/- 4 g min-1 100 g-1 (P less than 0.01) after the administration of the lower dose of thyrotropin-releasing hormone and from 64 +/- 5 to 112 +/- 17 g min-1 100 g-1 (P less than 0.01) after the higher dose. In the conscious animals, yohimbine caused an increase in mean arterial blood pressure and heart rate. Vascular resistance increased in several organs. The cerebral blood flow decreased in white matter (P less than 0.05) and the caudate nucleus (P less than 0.05). The results indicate that there is a yohimbine-sensitive mechanism involved in the cerebrovasodilating effect of thyrotropin-releasing hormone in anaesthetized rabbits.(ABSTRACT TRUNCATED AT 250 WORDS)

Place, publisher, year, edition, pages
1991. Vol. 143, no 2, p. 187-194
National Category
Physiology
Identifiers
URN: urn:nbn:se:umu:diva-167525DOI: 10.1111/j.1748-1716.1991.tb09220.xISI: A1991GH96100006PubMedID: 1683737OAI: oai:DiVA.org:umu-167525DiVA, id: diva2:1388082
Available from: 2020-01-23 Created: 2020-01-23 Last updated: 2020-01-24Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textPubMed

Authority records BETA

Koskinen, Lars-Owe D.

Search in DiVA

By author/editor
Koskinen, Lars-Owe D.
In the same journal
Acta Physiologica Scandinavica
Physiology

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf