Document Detail


The effects of paraoxon on blood pressure in the anaesthetized and in the conscious rat.
MedLine Citation:
PMID:  7139183     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
1 Intravenous administration of paraoxon (150-825 mug/kg) to anaesthetized rats induced long-lasting, dose-dependent pressor effects. Only after injection of 825 mug/kg paraoxon was the pressor response followed by a depressor effect and a bradycardia that could be blocked by N-methylatropine. Intracerebroventricular injection of paraoxon into anaesthetized rats also induced pressor effects.2 In order to elucidate the mechanism of the pressor action rats were given dexetimide, N-methylatropine, mecamylamine, phentolamine, prazosin, yohimbine, atenolol and metoprolol. If treatment with these drugs resulted in a low initial blood pressure, vasopressin was infused to elevate blood pressure to normal levels. The influence of adrenalectomy, pretreatment with reserpine and midcollicular transection was also examined.3 The pressor effect of paraoxon was not influenced by N-methylatropine or mecamylamine. However, a combination of these drugs as well as dexetimide, phentolamine or prazosin combined with yohimbine, reduced or prevented the pressor effect.4 In conscious rats the effects of paraoxon and the action of antimuscarinic drugs upon the pressor response were similar to those observed in anaesthetized animals.5 Acetylcholinesterase activities were measured in various brain regions and in whole blood. Paraoxon concentrations within the CNS were also measured.6 It is concluded that the pressor effect of paraoxon in anaesthetized and conscious rats is mediated by a central mechanism, although a contribution of peripheral acetylcholinesterase inhibition in sympathetic ganglia to this pressor effect cannot be ruled out.
Authors:
J H De Neef; K M Jordaan; A J Porsius
Related Documents :
7622853 - Plasma adrenaline responses to long-term modification of blood pressure in normotensive...
9192903 - Enalapril and pressure-diuresis in hypertensive rats transgenic for mouse renin gene.
21695283 - Aliskiren/amlodipine combination for the treatment of hypertension.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  British journal of pharmacology     Volume:  77     ISSN:  0007-1188     ISO Abbreviation:  Br. J. Pharmacol.     Publication Date:  1982 Oct 
Date Detail:
Created Date:  1983-01-19     Completed Date:  1983-01-19     Revised Date:  2009-11-18    
Medline Journal Info:
Nlm Unique ID:  7502536     Medline TA:  Br J Pharmacol     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  223-32     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Acetylcholinesterase / metabolism
Adrenalectomy
Anesthesia
Animals
Blood Pressure / drug effects*
Decerebrate State
Injections, Intraventricular
Male
Paraoxon / pharmacology*
Rats
Rats, Inbred Strains
Reserpine / pharmacology
Time Factors
Chemical
Reg. No./Substance:
311-45-5/Paraoxon; 50-55-5/Reserpine; EC 3.1.1.7/Acetylcholinesterase
Comments/Corrections

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


Previous Document:  Human dermal collagen allografts: a three year histological study.
Next Document:  The pressor effects of paraoxon in the pithed rat.