Document Detail

Effect of captopril on sympathetic preganglionic efferent activity in cats.
MedLine Citation:
PMID:  8447450     Owner:  NLM     Status:  MEDLINE    
In 13 decerebrate cats, we studied the effects of captopril (10 mg/kg iv bolus) on the background discharge of thoracic preganglionic sympathetic fibers. After drug administration there was an initial reduction in systolic arterial pressure (SAP), which was followed by a later inhibition of sympathetic discharge (from 2.7 +/- 0.5 to 0.79 +/- 0.1 imp/0.1 s; P < 0.01). Captopril significantly reduced the excitatory response of sympathetic fibers to premature ventricular contraction (70 +/- 17 vs. 257 +/- 30%), inferior vena cava obstruction (176 +/- 56 vs. 315 +/- 85%) and asphyxia (143 +/- 20 vs. 245 +/- 51%). Vice versa the sympathetic response to aortic occlusion was unaffected (-58 +/- 8 vs. -62 +/- 6%). A similar reduction in sympathetic discharge was observed after captopril administration in anesthetized cats (n = 3). On the contrary, no changes in background neural discharge were noticed in decerebrate-spinalized cats (n = 5), despite comparable hemodynamic effects. These data indicate that captopril reduces sympathetic efferent activity and its responsiveness to excitatory stimuli. The lack of neural effects in decerebrate-spinalized cats is consistent with a brain stem site of action of captopril.
N Montano; T Gnecchi-Ruscone; M Contini; M L Finocchiaro; F Lombardi; A Malliani
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  The American journal of physiology     Volume:  264     ISSN:  0002-9513     ISO Abbreviation:  Am. J. Physiol.     Publication Date:  1993 Feb 
Date Detail:
Created Date:  1993-04-06     Completed Date:  1993-04-06     Revised Date:  2003-11-14    
Medline Journal Info:
Nlm Unique ID:  0370511     Medline TA:  Am J Physiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  H345-51     Citation Subset:  IM    
Centro Ricerche Cardiovascolari, Università di Milano, Italy.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Captopril / pharmacology*
Decerebrate State
Efferent Pathways / drug effects,  physiology
Ganglia, Sympathetic / drug effects*,  physiology
Reflex / drug effects
Reg. No./Substance:

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

Previous Document:  Complement C5a-mediated myocardial ischemia and neutrophil sequestration: two independent phenomena.
Next Document:  Tachyphylaxis to the vasopressor effects of endothelin in rat aortic rings.