Document Detail

Characterisation of the cardiovascular pharmacology of medetomidine in the horse and sheep.
MedLine Citation:
PMID:  9839894     Owner:  NLM     Status:  MEDLINE    
Medetomidine was administered to sheep and horses at a dose rate of 5 microg kg(-1) (i.v.). Heart rate and blood pressure were recorded. Medetomidine induced bradycardia and a biphasic blood pressure response consisting of a transient hypertension followed by hypotension. Administration of prazosin (an alpha1 adrenoceptor antagonist; 100 microg kg(-1), i.v.) had no effect on the cardiovascular response to medetomidine (5 microg kg(-1), i.v.), but inhibited the cardiovascular response of methoxamine (an alpha1 adrenoceptor agonist; 75 microg kg(-1), i.v.). L-659,066 (an alpha2 adrenoceptor antagonist which does not cross the blood brain barrier; 264 microg kg(-1), i.v.) attenuated the medetomidine induced bradycardia, but had no effect on the cardiovascular response to methoxamine. L659,066 also reduced the medetomidine induced hypertension in sheep, but had less effect on the horse. It is concluded that both alpha1 and alpha2 adrenoceptors are important in the control of cardiovascular function in horses and sheep. Medetomidine appears to act on alpha2 adrenoceptors alone in the sheep. The cardiovascular effects of medetomidine in the horse are complex and may be influenced by central alpha2 adrenoceptor regulation or effects on other receptor subtypes as well as direct stimulation of peripheral alpha2 adrenoceptors.
C E Bryant; J Thompson; K W Clarke
Related Documents :
10869394 - Protective effects of i(1)-antihypertensive agent moxonidine against neurogenic cardiac...
1350994 - Cardiovascular responses of sinoaortic-denervated rats to intracerebroventricular injec...
1121054 - The mean circulatory pressure, reproducibility of its measurements and the effect of ph...
2559974 - Role of central opiate receptor subtypes in the circulatory responses of awake rabbits ...
9422294 - Should nitrous oxide be discontinued before desflurane after anaesthesia with desfluran...
8229584 - Intrathoracic silo for fetal diaphragmatic hernia: lung growth and slow reduction of ab...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Research in veterinary science     Volume:  65     ISSN:  0034-5288     ISO Abbreviation:  Res. Vet. Sci.     Publication Date:    1998 Sep-Oct
Date Detail:
Created Date:  1999-02-12     Completed Date:  1999-02-12     Revised Date:  2009-09-29    
Medline Journal Info:
Nlm Unique ID:  0401300     Medline TA:  Res Vet Sci     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  149-54     Citation Subset:  IM    
Department of Farm Animal and Equine Medicine and Surgery, The Royal Veterinary College, The University of London, Hatfield, Herts.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Adrenergic alpha-Agonists / administration & dosage,  pharmacology*
Adrenergic alpha-Antagonists / pharmacology
Blood Pressure / drug effects*
Heart Rate / drug effects*
Horses / physiology*
Imidazoles / administration & dosage,  pharmacology*
Injections, Intravenous
Prazosin / pharmacology
Quinolizines / pharmacology
Sheep / physiology*
Grant Support
//Wellcome Trust
Reg. No./Substance:
0/Adrenergic alpha-Agonists; 0/Adrenergic alpha-Antagonists; 0/Imidazoles; 0/Quinolizines; 114914-42-0/L 659066; 19216-56-9/Prazosin; 86347-14-0/Medetomidine

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Postnatal evolution of lymphocyte subpopulations in peripheral blood and lymphoid organs in the goat...
Next Document:  In vitro generation of equine osteoclasts from bone marrow cells using a novel culture system.