The effect of quinidine and myocardial ischemia on the isolated rat heart with fat-free diet

M. S. Merkin, E. M. Berry, A. Shefer, Y. Hasin

Research output: Contribution to journalArticlepeer-review


Fat-free diet changes the lipid content and the electrophysiological properties of the rat myocardium. Five percent fat supplementation to the diet does not alter the basic electrophysiological properties but still has a biochemical effect on the lipid content of the myocardium. The purpose of this work was to determine whether these biochemical alterations affect the response of the myocardium to quinidine and ischemia, both of which interact with the lipid component of the membrane. We used strength-duration, strength-interval and threshold of ventricular fibrillation to measure the electrophysiological properties of the isolated rat heart at baseline and after 30 minutes of quinidine perfusion or coronary artery ligation. The fatty acid composition of the myocardium was analyzed. We found that a fat-free diet caused essential fatty-acid deficiency, while 5% fat supplementation had a partial protective effect. Quinidine decreased excitability and increased refractoriness in both groups but had more effect on the fat-free diet hearts group. There was no difference in the ventricular fibrillation threshold Ischemia increased myocardial excitability in the fat-free diet hearts group and had no effect on refractoriness or ventricular fibrillation threshold. These results support the theory that the lipid composition of the myocardial membrane affects its response to lipophilic drugs and ischemia.

Original languageEnglish
Pages (from-to)133-150
Number of pages18
JournalJournal of Basic and Clinical Physiology and Pharmacology
Issue number2
StatePublished - Apr 1994
Externally publishedYes


  • essential fatty acid deficiency
  • myocardial ischemia
  • quinidine


Dive into the research topics of 'The effect of quinidine and myocardial ischemia on the isolated rat heart with fat-free diet'. Together they form a unique fingerprint.

Cite this