Calcium-Channel Blocker, Calcium Release-related Contractile Dysfunction (Ryanopathy) and Calcium as Neurotransmitter Sensor
Author, and Content Consultant to e-SERIES A: Cardiovascular Diseases: Justin Pearlman, MD, PhD, FACC
Author and Curator: Larry H Bernstein, MD, FCAP

Image created by Adina Hazan 06/30/2021
Introduction
Author: Larry H Bernstein, MD, FACC
http://dx.doi.org/10.1113/jphysiol.2008.160440. Epub 2008 Sep 11.)
Figure 5. Vascular or airway SMCs are driven by a cytosolic oscillator that generates a periodic release of Ca2+ from the endoplasmic reticulum that usually appears as a propagating Ca2+ wave. From: Smooth muscle cell calcium activation mechanisms.
The oscillator is induced/modulated by neurotransmitters such as acetylcholine (ACh), 5-hydroxytryptamine (5-HT), noradrenaline (NA) and endothelin-1 (ET-1), which act through inositol 1,4,5-trisphosphate (InsP3) that initiates the oscillatory mechanism. The sequence of steps 1–9 is described in the text. Reproduced from Berridge (2008), with permission.
Michael J Berridge. J Physiol. 2008 November 1;586(Pt 21):5047-5061. http://www.ncbi.nlm.nih.gov/pmc/articles/instance/2652144/bin/tjp0586-5047-f5.jpg
Figure 7. The cytosolic Ca2+ oscillator responsible for pacemaker activity in interstitial cells of Cajal releases periodic pulses of Ca2+ that form a Ca2+ wave. From: Smooth muscle cell calcium activation mechanisms.
The increase in Ca2+ activates Cl− channels (CLCA) to give the spontaneous transient inward currents (STICs) that sum to form the spontaneous transient depolarizations (STD) resulting in the slow waves of membrane depolarization (see inset). Current flow through gap junctions allows these waves to spread into neighbouring smooth muscle cells to activate contraction. See text for a description of the oscillator that drives this activation process. Reproduced from Berridge (2008), with permission.
Michael J Berridge. J Physiol. 2008 November 1;586(Pt 21):5047-5061. http://www.ncbi.nlm.nih.gov/pmc/articles/instance/2652144/bin/tjp0586-5047-f7.gif
This article is the Part IX in a series of articles on Activation and Dysfunction of the Calcium Release Mechanisms in Cardiomyocytes and Vascular Smooth Muscle Cells.
The Series consists of the following articles:
Part I: Identification of Biomarkers that are Related to the Actin Cytoskeleton
Larry H Bernstein, MD, FCAP
Part II: Role of Calcium, the Actin Skeleton, and Lipid Structures in Signaling and Cell Motility
Larry H. Bernstein, MD, FCAP, Stephen Williams, PhD and Aviva Lev-Ari, PhD, RN
Part III: Renal Distal Tubular Ca2+ Exchange Mechanism in Health and Disease
Larry H. Bernstein, MD, FCAP, Stephen J. Williams, PhD and Aviva Lev-Ari, PhD, RN
Part IV: The Centrality of Ca(2+) Signaling and Cytoskeleton Involving Calmodulin Kinases and Ryanodine Receptors in Cardiac Failure, Arterial Smooth Muscle, Post-ischemic Arrhythmia, Similarities and Differences, and Pharmaceutical Targets
Larry H Bernstein, MD, FCAP, Justin Pearlman, MD, PhD, FACC and Aviva Lev-Ari, PhD, RN
Part V: Ca2+-Stimulated Exocytosis: The Role of Calmodulin and Protein Kinase C in Ca2+ Regulation of Hormone and Neurotransmitter
Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN
Part VI: Calcium Cycling (ATPase Pump) in Cardiac Gene Therapy: Inhalable Gene Therapy for Pulmonary Arterial Hypertension and Percutaneous Intra-coronary Artery Infusion for Heart Failure: Contributions by Roger J. Hajjar, MD
Aviva Lev-Ari, PhD, RN
Part VII: Cardiac Contractility & Myocardium Performance: Ventricular Arrhythmiasand Non-ischemic Heart Failure – Therapeutic Implications for Cardiomyocyte Ryanopathy (Calcium Release-related Contractile Dysfunction) and Catecholamine Responses
Justin Pearlman, MD, PhD, FACC, Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN
Part VIII: Disruption of Calcium Homeostasis: Cardiomyocytes and Vascular Smooth Muscle Cells: The Cardiac and Cardiovascular Calcium Signaling Mechanism
Justin Pearlman, MD, PhD, FACC, Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN
Part IX: Calcium-Channel Blockers, Calcium Release-related Contractile Dysfunction (Ryanopathy) and Calcium as Neurotransmitter Sensor
Justin Pearlman, MD, PhD, FACC, Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN
Part X: Synaptotagmin functions as a Calcium Sensor: How Calcium Ions Regulate the fusion of vesicles with cell membranes during Neurotransmission
Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN
Part XI: Sensors and Signaling in Oxidative Stress
Larry H. Bernstein, MD, FCAP
http://pharmaceuticalintelligence.com/2013/11/01/sensors-and-signaling-in-oxidative-stress/
Part XII: Atherosclerosis Independence: Genetic Polymorphisms of Ion Channels Role in the Pathogenesis of Coronary Microvascular Dysfunction and Myocardial Ischemia (Coronary Artery Disease (CAD))
Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN
This article has FIVE Sections:
Section One
Innovations in Combination Drug Therapy: Calcium-Channel Blocker – Amlodipine (Norvasc) in single-pill combinations (SPCs) of drugs
Section Two
Calcium-Channel Blockers: Drug Class and Indications
Section Three
Brand and Generic Calcium Channel Blocking Agents
Section Four
Dysfunction of the Calcium Release Mechanism
Section Five
The Calcium Sensor: How Calcium Ions Regulate the fusion of vesicles with cell membranes during Neurotransmission
Innovations in Combination Drug Therapy:
Calcium-Channel Blocker, Amlodipine (Norvasc) in Single-Pill Combinations (SPCs) of Drugs
- telmisartan/amlodipine (T/A) [ARB/CCB]
and
- telmisartan/hydrochlorothiazide (T/H) [ARB/Diuterics]
CCB – amlodipine
Diuretics – hydrochlorothiazide
A review of the benefits of early treatment initiation with single-pill combinations of telmisartan with amlodipine or hydrochlorothiazide
Authors: Segura J, Ruilope LM
Published Date September 2013 Volume 2013:9 Pages 521 – 528
http://www.dovepress.com/articles.php?article_id=14373
Published: | 16 September 2013, Dovepress Journal: Vascular Health and Risk Management |
---|
Julian Segura, Luis Miguel Ruilope
Department of Nephrology, Hospital 12 de Octubre, Madrid, Spain
Abstract:
- Compared with the respective monotherapies, the once-daily T/A and T/H SPCs have been shown to result in significantly higher blood pressure (BP) reductions, BP goal rates, and response rates in patients at all stages of hypertension.
- As expected, BP reductions are highest with the highest dose (T80/A10 and T80/H25) SPCs. Subgroup analyses of the telmisartan trials have reported the efficacy of both SPCs to be consistent, regardless of the patients’ age, race, and coexisting diabetes, obesity, or renal impairment.
- In patients with mild-to-moderate hypertension, the T/A combination provides superior 24-hour BP-lowering efficacy compared with either treatment administered as monotherapy.
- Similarly, the T/H SPC treatment provides superior 24-hour BP-lowering efficacy, especially in the last 6 hours relative to other renin–angiotensin system inhibitor-based SPCs.
- The T/A SPC is associated with a lower incidence of edema than amlodipine monotherapy, and
- The T/H SPC with a lower incidence of hypokalemia than hydrochlorothiazide monotherapy
- Existing evidence supports the use of the T/A SPC for the treatment of hypertensive patients with prediabetes, diabetes, or metabolic syndrome, due to the metabolic neutrality of both component drugs, and the use of the T/H SPC for those patients with edema or in need of volume reduction.
We reported on 5/29/2012
Triple Combination Therapy: ARB and Calcium Channel Blocker and Diuretics
In July 2010, a triple combination drug for hypertension was approved by the US Food and Drug Administration. Tribenzor contains olmesartan medoxomil, amlodipine and hydrochlorothiazide, according to Monthly Prescribing Reference.
TRIBENZOR is a Daiichi Sankyo’s product- ARB and Calcium Channel Blocker and Diuretic
How TRIBENZOR work
Tribenzor contains olmesartan medoxomil, amlodipine and hydrochlorothiazide. High blood pressure makes the heart work harder to pump blood through the body and causes damage to blood vessels. TRIBENZOR can help your blood vessels relax and reduce the amount of fluid in your blood. This can make your blood pressure lower. Medicines that lower blood pressure may lower your chance of having a stroke or a heart attack.
Some people may need more than 1—or even more than 2—medicines to help control their blood pressure. TRIBENZOR combines 3 effective medicines in 1 convenient pill. Read the following chart to learn how each medicine works in its own way to help lower blood pressure.
TRIBENZOR: 3 effective medicines in 1 pill
The medicine in TRIBENZOR | How it works | What it does |
Angiotensin II receptor blocker | Blocks a natural chemical in your body that causes blood vessels to narrow. |
Lowers Yours blood pressure |
Calcium channel blocker | Blocks the narrowing effect of calcium on your blood vessels. This helps your blood vessels relax. | |
Diuretic (water pill) | Helps your kidneys flush extra fluid and salt from your body. This lowers the amount of fluid in your blood. |
http://www.tribenzor.com/how_works.html
Effectively lower blood pressure. People taking the 3 medicines in TRIBENZOR had greater reductions in blood pressure than did people taking any 2 of the medicines combined
Start to work quickly. People taking TRIBENZOR saw results in as little as 2 weeks
AZOR is a Daiichi Sankyo’s product- ARB and Calcium Channel Blocker
How AZOR work
AZOR relaxes and widens blood vessels to help lower blood pressure.
You may have already tried another blood pressure medicine that works a certain way to lower blood pressure. But 1 blood pressure medicine may not be enough for you. You may find the help you need with the 2 effective medicines in AZOR.
AZOR combines 2 effective medicines in 1 convenient pill.
Learn how each medicine in AZOR works in its own way to help lower blood pressure.
The medicine in AZOR | How it works | What it does |
Angiotensin II receptor blocker (ARB) | Blocks a natural chemical in your body that causes blood vessels to narrow. This helps your blood vessels relax and widen. |
Lowers Your Blood pressure |
Calcium channel blocker | Blocks the narrowing effect of calcium on your blood vessels. This helps your blood vessels relax. |
Calcium-Channel Blockers: Drug Class and Indications
In Sudhof’s Lasker Award presentation he refers to the biochemical properties of synaptotagmin were found to precisely correspond to the extraordinary calcium-triggering properties of release, and to account for a regulatory pathway that also applies to other types of calcium-triggered fusion, for example fusion observed in hormone secretion. A CCB would have to block the calcium-triggering properties of release, and consequently, would block the release of neurohormones. This is because the fusion apparatus and its synaptotagmin-dependent control mechanism linked to the calcium channels, docking and priming synaptic vesicles, being blocked, disables the calcium-control of the vesicle fusion that is necessary for neurotransmitter release. Consequently, the end result would be increased vascular flow from the inhibition.
What are calcium channel blockers and how do they work?
In order to pump blood, the heart needs oxygen. The harder the heart works, the more oxygen it requires. Angina (heart pain) occurs when the supply of oxygen to the heart is inadequate for the amount of work the heart must do. By dilating the arteries, CCBs reduce the pressure in the arteries. This makes it easier for the heart to pump blood, and, as a result, the heart needs less oxygen. By reducing the heart’s need for oxygen, CCBs relieve or prevent angina. CCBs also are used for treating high blood pressure because of their blood pressure-lowering effects. CCBs also slow the rate at which the heart beats and are therefore used for treating certain types of abnormally rapid heart rhythms.
For what conditions are calcium channel blockers used?
CCBs are used for treating high blood pressure, angina, and abnormal heart rhythms (for example, atrial fibrillation, paroxysmal supraventricular tachycardia).
They also may be used after a heart attack, particularly among patients who cannot tolerate beta-blocking drugs, have atrial fibrillation, or require treatment for their angina.
Unlike beta blockers, CCBs have not been shown to reduce mortality or additional heart attacks after a heart attack.
CCBs are as effective as ACE inhibitors in reducing blood pressure, but they may not be as effective as ACE inhibitors in preventing the kidney failure caused by high blood pressure or diabetes.
They also are used for treating:
- pulmonary hypertension,
- Raynaud’s syndrome,
- cardiomyopathy, and
- subarachnoid hemorrhage.
CCBs are also used in the prevention of migraine headaches.
Are there any differences among calcium channel blockers?
CCBs differ in their duration of action, the process by which they are eliminated from the body, and, most importantly, in their ability to affect heart rate and contraction. Some CCBs [for example, amlodipine (Norvasc)] have very little effect on heart rate and contraction so they are safer to use in individuals who have heart failure or bradycardia (a slow heart rate). Verapamil (Calan, Isoptin) and diltiazem (Cardizem) have the greatest effects on the heart and reduce the strength and rate of contraction. Therefore, they are used in reducing heart rate when the heart is beating too fast.
What are the side effects of calcium channel blockers?
- The most common side effects of CCBs are constipation, nausea,headache, rash, edema (swelling of the legs with fluid), low blood pressure, drowsiness, and dizziness.
- Liver dysfunction and over growth of gums may also occur. When diltiazem (Cardizem) or verapamil (Calan, Isoptin) are given to individuals with heart failure, symptoms of heart failure may worsen because these drugs reduce the ability of the heart to pump blood.
- Like other blood pressure medications, CCBs are associated with sexual dysfunction.
http://www.medicinenet.com/calcium_channel_blockers/article.htm
Section Three
Brand and Generic Calcium Channel Blocking Agents
A drug may be classified by the chemical type of the active ingredient or by the way it is used to treat a particular condition. Each drug can be classified into one or more drug classes.
Calcium channel blockers block voltage gated calcium channels and inhibits the influx of calcium ions into cardiac and smooth muscle cells. The decrease in intracellular calcium reduces the strength of heart muscle contraction, reduces conduction of impulses in the heart, and causes vasodilatation.
Decrease in intracellular calcium in the heart decreases cardiac contractility. Decreased calcium in the vascular smooth muscle reduces its contraction and therefore causes vasodilatation.
Decrease in cardiac contractility decreases cardiac output and vasodilatation decreases total peripheral resistance, both of which cause a drop in blood pressure.
Calcium channel blocking agents are used to treat hypertension.
Filter by: — all conditions –AnginaAngina Pectoris ProphylaxisArrhythmiaAtrial FibrillationAtrial FlutterBipolar DisorderCluster HeadachesCoronary Artery DiseaseHeart FailureHigh Blood PressureHypertensive EmergencyHypertrophic CardiomyopathyIdiopathic Hypertrophic Subaortic StenosisIschemic StrokeMigraine PreventionNocturnal Leg CrampsPremature LaborRaynaud’s SyndromeSubarachnoid HemorrhageSupraventricular Tachycardia
Section Four
Dysfunction of the Calcium Release Mechanism
For Disruption of Calcium Homeostasis in Vascular Smooth Muscle Cells, see
Part IV: The Centrality of Ca(2+) Signaling and Cytoskeleton Involving Calmodulin Kinases and Ryanodine Receptors in Cardiac Failure, Arterial Smooth Muscle, Post-ischemic Arrhythmia, Similarities and Differences, and Pharmaceutical Targets
Larry H Bernstein, MD, FCAP, Justin Pearlman, MD, PhD, FACC and Aviva Lev-Ari, PhD, RN
Part V: Heart, Vascular Smooth Muscle, Excitation-Contraction Coupling (E-CC), Cytoskeleton, Cellular Dynamics and Ca2 Signaling
Larry H Bernstein, MD, FCAP, Justin Pearlman, MD, PhD, FACC and Aviva Lev-Ari, PhD, RN
For Disruption of Calcium Homeostasis in Cardiomyocyte Cells, see
Part VI: Calcium Cycling (ATPase Pump) in Cardiac Gene Therapy: Inhalable Gene Therapy for Pulmonary Arterial Hypertension and Percutaneous Intra-coronary Artery Infusion for Heart Failure: Contributions by Roger J. Hajjar, MD
Aviva Lev-Ari, PhD, RN
Part VII: Cardiac Contractility & Myocardium Performance: Ventricular Arrhythmias and Non-ischemic Heart Failure – Therapeutic Implications for Cardiomyocyte Ryanopathy (Calcium Release-related Contractile Dysfunction) and Catecholamine Responses
Justin Pearlman, MD, PhD, FACC, Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN
Part VIII: Disruption of Calcium Homeostasis: Cardiomyocytes and Vascular Smooth Muscle Cells: The Cardiac and Cardiovascular Calcium Signaling Mechanism
Justin Pearlman, MD, PhD, FACC, Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN
Section Five
The Calcium Sensor: How Calcium Ions Regulate the fusion of vesicles with cell membranes during Neurotransmission
This topic is covered in
Synaptotagmin functions as a Calcium Sensor: How Calcium Ions Regulate the fusion of vesicles with cell membranes during Neurotransmission
Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN
Part V: Heart, Vascular Smooth Muscle, Excitation-Contraction Coupling (E-CC), Cytoskeleton, Cellular Dynamics and Ca2 Signaling
Larry H Bernstein, MD, FCAP, Justin Pearlman, MD, PhD, FACC and Aviva Lev-Ari, PhD, RN
Summary
Work on neurotransmitter release revealed a hierarchy of molecular machines that mediate the fusion of synaptic vesicles, the calcium-control of this fusion, and the embedding of calcium-controlled fusion in the context of the presynaptic terminal at the synapse. The neural transmission is described as a biological relay system. Neurotransmission kicks off with an electrical pulse that runs down a nerve cell, or neuron. When that signal reaches the tip, calcium enters the cell. In response, the neuron liberates chemical messengers—neurotransmitters. When the calcium-controlled fusion at the presynaptic junction is blocked, as with a CCB, neurotransmitters are not released. The activity of the neurotransmitters would be to cause smaooth muscle contraction of the vessel. The CCB would cause relaxation and flow.
http://www.nature.com/focus/Lasker/2013/pdf/ES-Lasker13-Sudhof.pdf
Part IX of this series of articles discussed the mechanism of the signaling of smooth muscle cells by the interacting parasympathetic neural innervation that occurs by calcium triggering neurotransmitter release by initiating synaptic vesicle fusion. It involves the interaction of soluble N-acetylmaleimide-sensitive factor (SNARE) and SM proteins, and in addition, the discovery of a calcium-dependent Syt1 (C) domain of protein- kinase C isoenzyme, which binds to phospholipids. It is reasonable to consider that it differs from motor neuron activation of skeletal muscles, mainly because the innervation is in the involuntary domain. The cranial nerve rooted innervation has evolved comes from the spinal ganglia at the corresponding level of the spinal cord. It is in this specific neural function that we find a mechanistic interaction with adrenergic hormonal function, a concept intimated by the late Richard Bing. Only recently has there been a plausible concept that brings this into serious consideration. Moreover, the review of therapeutic drugs that are used in blocking adrenergic receptors are closely related to the calcium-channels. Interesting too is the participation of a phospholipid bound protein-kinase isoenzyme C calcium-dependent domain Syt1. The neurohormonal connection lies in the observation by Katz in the 1950’s that the vesicles of the neurons hold and eject fixed amounts of neurotransmitters. The mechanism of this action will be futher discussed in Part X.
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