Document Detail

Contrasting effects of verapamil and nifedipine on pH of ischemic myocardium in the dog.
MedLine Citation:
PMID:  2918474     Owner:  NLM     Status:  MEDLINE    
It remains unknown whether the actions of verapamil to depress and nifedipine to enhance contractile function of ischemic myocardium influence the degree of myocardial ischemic injury. Thus, we measured intramyocardial pH using fiberoptic pH probes in 43 anesthetized open-chest dogs pretreated for 30 min with verapamil, or nifedipine in doses that decreased aortic pressure 10 to 15 mm Hg before ligation of the left anterior descending coronary artery for 15 min. Drugs were continued during the 15-min ischemic period until the animals were euthanized without reperfusion: verapamil, 10-20 micrograms/kg/min and nifedipine, 2 to 4 micrograms/kg/min i.v. Verapamil-treated dogs showed higher pH of ischemic subendocardium after 15 min ischemia (6.75 +/- 0.07) than did the nifedipine (6.48 +/- 0.04) or placebo (6.43 +/- 0.05) groups, even if the animals were paced (6.71 +/- 0.11) to prevent the negative chronotropic effect of verapamil (P less than 0.01). Neither verapamil nor nifedipine changed collateral myocardial blood flow from 0.10 +/- 0.02 in the subendocardium and 0.17 +/- 0.03 ml/min/g in the subepicardium. Left ventricular function estimated by left ventricular dp/dt was depressed 15% by verapamil and enhanced 26% by nifedipine. Thus, verapamil, but not nifedipine, relieves acidosis of ischemic myocardium after acute coronary occlusion in doses that sustain a 10 to 15 mm Hg decrease in aortic pressure. Nifedipine, in doses that produced the same 10 to 15 mm Hg decrease in mean aortic pressure, did not increase intramyocardial pH, as it enhanced contractile function, estimated by left ventricular dp/dt.(ABSTRACT TRUNCATED AT 250 WORDS)
Y M Ro; D R Markle; S R Goldstein; E Speir; R Greene; K Steadman; R Aamodt; S E Epstein; R E Patterson
Related Documents :
3391034 - A comparative study of the acute antihypertensive effect of adalat capsules and corinfa...
9585114 - Effects of cd-832, a new calcium antagonist, on intracranial pressure in anesthetized d...
8316404 - Skin flux and the venoarteriolar response in essential hypertension.
3653084 - Bupivacaine accentuates the cardiovascular depressant effects of verapamil in conscious...
15277214 - Regulation of fibrillin-1 by biglycan and decorin is important for tissue preservation ...
21253044 - Blood pressure measurement by family physicians.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  The Journal of pharmacology and experimental therapeutics     Volume:  248     ISSN:  0022-3565     ISO Abbreviation:  J. Pharmacol. Exp. Ther.     Publication Date:  1989 Feb 
Date Detail:
Created Date:  1989-04-03     Completed Date:  1989-04-03     Revised Date:  2014-05-29    
Medline Journal Info:
Nlm Unique ID:  0376362     Medline TA:  J Pharmacol Exp Ther     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  654-60     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Coronary Circulation / drug effects
Coronary Disease / drug therapy,  metabolism*
Hemodynamics / drug effects
Hydrogen-Ion Concentration
Myocardial Contraction / drug effects
Myocardium / metabolism*
Nifedipine / pharmacology*,  therapeutic use
Verapamil / pharmacology*
Reg. No./Substance:
CJ0O37KU29/Verapamil; I9ZF7L6G2L/Nifedipine

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

Previous Document:  Studies on inhibition of angiotensin II receptors in rabbit adrenal and aorta.
Next Document:  Block of 45Ca uptake into synaptosomes by methylmercury: Ca++- and Na+-dependence.