Document Detail

Correlation between fall in blood pressure and in vivo amine release after alpha-methylDOPA.
MedLine Citation:
PMID:  2767124     Owner:  NLM     Status:  MEDLINE    
Blood pressure (BP), hypothalamic tissue concentrations and the in vivo overflow of endogenous and alpha-methylated catecholamines were measured in urethane anaesthetised rats after alpha-methylDOPA (mDOPA) administration (200 mg/kg i.p.). Four hours after mDOPA, BP fell to its lowest value, 60% of control, and slowly returned towards control levels by 24 h. This was closely correlated with the evoked overflow of alpha-methylnoradrenaline (mNA, r = 0.9) and noradrenaline (NA, r = 0.7) but not dopamine (DA) or alpha-methyldopamine (mDA). However, the tissue content of mNA rose much more gradually and was not maximal until after 12 h while mDA content followed the development of the hypotension. The results provide direct evidence for a false transmitter role for mNA in the brain, and suggest that the release of newly synthesised mNA is responsible for the hypotensive effect of mDOPA. Differences in the time course of overflow and storage of NA and mNA suggest the presence of separate transmitter storage and releasable pools.
V Kapoor; J Chalmers
Related Documents :
2568144 - 8-oh-dpat, flesinoxan and guanfacine: systemic and regional haemodynamic effects of cen...
2856814 - Differences between exogenous and endogenous noradrenaline in the effects on vascular p...
348364 - Clinical dose-response studies with guanfacine (bs 100-141), a new antihypertensive agent.
477484 - The influence of clonidine on intraocular pressure.
15278494 - The effects of an intravenous nicardipine injection on baroreflex control of heart rate...
11323814 - Estimation of relative cardiovascular pressures using time-resolved three-dimensional p...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  European journal of pharmacology     Volume:  164     ISSN:  0014-2999     ISO Abbreviation:  Eur. J. Pharmacol.     Publication Date:  1989 May 
Date Detail:
Created Date:  1989-10-05     Completed Date:  1989-10-05     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  1254354     Medline TA:  Eur J Pharmacol     Country:  NETHERLANDS    
Other Details:
Languages:  eng     Pagination:  531-8     Citation Subset:  IM    
Department of Medicine, Flinders Medical Centre, Bedford Park, South Australia.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Biogenic Amines / metabolism*
Blood Pressure / drug effects*
Catecholamines / metabolism
Hypothalamus / drug effects,  metabolism
Methyldopa / pharmacology*
Potassium / pharmacology
Rats, Inbred SHR
Reg. No./Substance:
0/Biogenic Amines; 0/Catecholamines; 555-30-6/Methyldopa; 7440-09-7/Potassium

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

Previous Document:  Effects of dantrolene sodium in rodent models of cardiac arrhythmia.
Next Document:  The protective action of R56865 against ouabain-induced intoxication in rat heart isolated atria and...