Related Experiment Video

Updated: Oct 9, 2026

Murine Isolated Heart Model of Myocardial Stunning Associated with Cardioplegic Arrest
08:30

Murine Isolated Heart Model of Myocardial Stunning Associated with Cardioplegic Arrest

Published on: August 6, 2015

Protection of ischemic hearts by Ca2+ antagonists

J A Watts

    Journal of Molecular and Cellular Cardiology
    |October 1, 1986
    PubMed

    Insights

    Calcium channel blockers like verapamil and diltiazem protect working rat hearts during ischemia by preserving energy stores and reducing calcium overload. Pretreatment before ischemia is crucial for this protective effect.

    Area of Science:

    • Cardiology
    • Pharmacology
    • Biochemistry

    Background:

    • Global ischemia significantly impairs heart function and energy stores.
    • Calcium channel blockers are known to affect cardiac function and energy metabolism.

    Purpose of the Study:

    • To investigate the protective effects of calcium channel blockers (verapamil, diltiazem, nifedipine, bepridil) on isolated rat hearts subjected to global ischemia.
    • To determine the optimal timing and mechanism of action for these protective effects.

    Main Methods:

    • Isolated working rat hearts were pretreated with equiactive concentrations of calcium channel blockers before global ischemia.
    • Contractile function, high-energy phosphate (HEP) stores, mitochondrial function, and calcium (Ca2+) overload were assessed post-reperfusion.
    • Lactate production was measured in normal and K+-arrested ischemic hearts.

    Main Results:

    • Pretreatment with verapamil, diltiazem, and nifedipine before ischemia enhanced recovery of contractile function and HEP stores.
    • Treatment during reperfusion alone did not improve recovery.
    • Bepridil did not preserve function, HEP, or mitochondrial function and did not reduce Ca2+ overload, with Ca2+ accumulating in mitochondria.
    • Diltiazem reduced lactate production during ischemia.

    Conclusions:

    • Calcium channel blockers administered before global ischemia offer significant protection to working rat hearts.
    • The protective mechanisms involve not only energy preservation but also reduction of Ca2+ overload during reperfusion and altered Ca2+ compartmentation during ischemia.
    • Bepridil appears less effective than other tested calcium channel blockers in this model.

    More Related Videos

    Postconditioning with Lactate-enriched Blood for Cardioprotection in ST-segment Elevation Myocardial Infarction05:26

    Postconditioning with Lactate-enriched Blood for Cardioprotection in ST-segment Elevation Myocardial Infarction

    Published on: May 28, 2019

    Protection of H9c2 Myocardial Cells from Oxidative Stress by Crocetin via PINK1/Parkin Pathway-Mediated Mitophagy07:40

    Protection of H9c2 Myocardial Cells from Oxidative Stress by Crocetin via PINK1/Parkin Pathway-Mediated Mitophagy

    Published on: May 26, 2023

    Related Concept Videos

    Antihypertensive Drugs: Action of Calcium Channel Blockers01:18

    Antihypertensive Drugs: Action of Calcium Channel Blockers

    Calcium ions are essential to contract smooth muscle cells in blood vessels. They enter these cells through voltage-dependent calcium channels, specifically L-type calcium channels in the cell membrane. These L-type calcium channels are integral to the excitation-contraction coupling process in smooth muscle. When a stimulus is received by smooth muscle cells, their membrane depolarizes. This alteration in membrane potential instigates the opening of L-type calcium channels. As a result,...
    Antiarrhythmic Drugs: Class IV Agents as Calcium Channel Blockers01:20

    Antiarrhythmic Drugs: Class IV Agents as Calcium Channel Blockers

    Class IV antiarrhythmic drugs, such as verapamil and diltiazem, block calcium channels. They primarily affect the heart, slowing the conduction in calcium-dependent tissues like the SA and AV nodes. These drugs manage reentrant supraventricular tachycardia (SVT) and reduce ventricular rate in atrial flutter/fibrillation.
    Verapamil, a calcium channel blocker, inhibits calcium movement across myocardial cell membranes and vascular smooth muscle. This results in the dilation of coronary and...
    Ischemic Heart Disease: Overview01:17

    Ischemic Heart Disease: Overview

    Ischemic heart disease occurs when the heart's blood supply dwindles, causing an ominous lack of oxygen and nutrients. This deficiency, stemming from reduced or obstructed blood flow, spells danger, leading to heart muscle damage and dysfunction.
    Atherosclerosis, the primary malefactor, orchestrates this dangerous condition. It manifests as the accumulation of fatty deposits, akin to insidious plaques, within arterial walls. As time elapses, these plaques metamorphose, hardening and narrowing...
    Antianginal Drugs: Calcium Channel Blockers and Ranolazine01:25

    Antianginal Drugs: Calcium Channel Blockers and Ranolazine

    Angina pectoris, a primary symptom of ischemic heart disease, requires careful pharmacological interventions. In this context, calcium channel blockers (CCBs) and ranolazine have emerged as crucial pharmacotherapeutic agents, providing deep insights into the complexities of angina management.
    CCBs, a diverse class that includes dihydropyridines (nifedipine) and diphenylalkylamines (verapamil and diltiazem), exert their effect by blocking calcium channels in cardiac and smooth muscle cells. This...
    Coronary Artery Disease V: Interprofessional Care01:27

    Coronary Artery Disease V: Interprofessional Care

    Interprofessional care for coronary artery disease includes pharmacological therapy and revascularization procedures.Pharmacological therapy for Coronary Artery Disease (CAD) aims to manage symptoms, prevent complications, and improve patient outcomes through various classes of medications:Antiplatelet Agents:Aspirin and Clopidogrel: These medications inhibit platelet aggregation, preventing blood clots, which is crucial for avoiding heart attacks and strokes. Doctors often prescribe these...
    Acute Coronary Syndrome IV: Interprofessional Care01:28

    Acute Coronary Syndrome IV: Interprofessional Care

    IntroductionThe management of Acute Coronary Syndrome (ACS) aims to minimize myocardial damage, preserve myocardial function, and prevent complications.Initial ManagementInpatient management involves continuous cardiac monitoring, preferably in an ICU, focusing on blood pressure, serum sodium, potassium, and creatinine levels, and urine output. Ongoing pharmacologic management is crucial for stabilizing the patient.Supplemental Oxygen: Administer supplemental oxygen if oxygen saturation is...