Related Experiment Video

Updated: May 6, 2026

Mesenteric Artery Contraction and Relaxation Studies Using Automated Wire Myography
07:51

Mesenteric Artery Contraction and Relaxation Studies Using Automated Wire Myography

Published on: September 22, 2011

28.4K

Microcirculation: what is the role of calcium antagonists?

P G Camici1

  • 1MRC Clinical Sciences Centre, Hammersmith Hospital, London, U.K.

European Heart Journal
|January 1, 1997
PubMed

Insights

Calcium antagonists benefit the heart by dilating coronary vessels and reducing intramyocardial pressure. Positron emission tomography helps understand these effects, explaining drug efficacy against ischemia.

Area of Science:

  • Cardiology
  • Pharmacology
  • Medical Imaging

Background:

  • Coronary microcirculation plays a vital role in myocardial oxygen supply.
  • Calcium antagonists are a class of drugs with known cardiovascular effects.
  • Understanding drug actions on the microvasculature is crucial for treating ischemic heart conditions.

Purpose of the Study:

  • To review the beneficial effects of calcium antagonists on coronary microcirculation.
  • To explore the mechanisms by which these drugs impact coronary resistance vessels and intramyocardial pressure.
  • To highlight the utility of positron emission tomography in assessing these effects.

Main Methods:

  • Review of existing literature on calcium antagonists and coronary microcirculation.
  • Discussion of vasodilating actions on coronary resistance vessels.
  • Analysis of effects on extravascular resistance, specifically intramyocardial pressure.
  • Presentation of positron emission tomography (PET) for non-invasive myocardial blood flow and flow reserve measurement.

Main Results:

  • Calcium antagonists exhibit vasodilating effects on coronary resistance vessels.
  • These drugs influence extravascular resistance, including intramyocardial pressure.
  • Positron emission tomography enables non-invasive assessment of myocardial blood flow and reserve.
  • PET imaging can elucidate the impact of drug therapies on coronary microcirculation.

Conclusions:

  • Calcium antagonists positively affect coronary microcirculation through vasodilation and modulation of intramyocardial pressure.
  • Positron emission tomography is a valuable tool for understanding the in vivo effects of calcium antagonists.
  • The actions of calcium antagonists on the coronary microcirculation provide insight into their effectiveness in treating ischemia and ischemia-reperfusion injury.

More Related Videos

Simultaneous Measurements of Intracellular Calcium and Membrane Potential in Freshly Isolated and Intact Mouse Cerebral Endothelium09:45

Simultaneous Measurements of Intracellular Calcium and Membrane Potential in Freshly Isolated and Intact Mouse Cerebral Endothelium

Published on: January 20, 2019

7.6K
Author Spotlight: Developing Parmodulins to Target Protease-Activated Receptors for Inflammation Control07:13

Author Spotlight: Developing Parmodulins to Target Protease-Activated Receptors for Inflammation Control

Published on: May 24, 2024

1.1K

Related Concept Videos

Calmodulin-dependent Signaling01:16

Calmodulin-dependent Signaling

Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
5.0K
Adrenergic Antagonists: Pharmacological Actions of ɑ-Receptor Blockers01:22

Adrenergic Antagonists: Pharmacological Actions of ɑ-Receptor Blockers

α-Adrenergic antagonists, known as α-blockers, exert their effects by inhibiting α-adrenoceptors, leading to specific physiological actions. α1-blockers and α2-blockers have distinct pharmacological actions and therapeutic applications.
α1-blockers: These drugs inhibit α1-adrenoceptors on smooth muscle cells, resulting in vasodilation. This vasodilation lowers blood pressure, making α1-blockers valuable in treating hypertension. Additionally,...
1.7K
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,...
2.4K
Antihypertensive Drugs: Vasodilators01:23

Antihypertensive Drugs: Vasodilators

Vasodilators, primarily affecting the smooth muscles within arterial and venous walls, are commonly used for hypertension treatment. Medications such as minoxidil and hydralazine primarily target arteries and arterioles, while sodium nitroprusside acts on arterioles and venules. Minoxidil, functioning as a prodrug, is metabolized by hepatic sulfotransferase into its active form, minoxidil sulfate, after oral administration. This metabolite binds to the sulfonylurea receptor (SUR) component of...
2.5K
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...
2.8K
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...
1.9K