Calcium channel; Permeability-glycoprotein (P-gp); CYP3A4[1]

EverFluor FL Verapamil (EFV) inhibits TR-iBRB2 cells in a concentration-dependent manner, while Verapamil inhibits them in a concentration-inhibitory manner with an IC50 of 98.0 μM [4].

In atrial fibrillation, verapamil (facial) can be used to control the atrioventricular nodal response and avoid atrioventricular reentrant tachycardia [2]. An intravenous injection of verapamil was given into the anterior chest region's femoral vein. Within 45 minutes following coronary artery closure, the incidence of ventricular arrhythmias, such as ventricular tachycardia (VT), ventricular fibrillation (VF), and premature ventricular contractions (PVCs), was considerably reduced by verapamil (1 mg/kg). An ischemic heart resulted in a considerable increase in the overall arrhythmia score. The administration of 1 mg/kg of verapamil effectively inhibited the rise in overall cardiovascular-induced arrhythmia scores [5].

Methods: EverFluor FL Verapamil (EFV) was adopted as the fluorescent probe of verapamil, and its transport across the BRB was investigated with common carotid artery infusion in rats. EFV transport at the inner and outer BRB was investigated with TR-iBRB2 cells and RPE-J cells, respectively. Results: The signal of EFV was detected in the retinal tissue during the weak signal of cell impermeable compound. In TR-iBRB2 cells, the localization of EFV differed from that of LysoTracker® Red, a lysosomotropic agent, and was not altered by acute treatment with NH4Cl. In RPE-J cells, the punctate distribution of EFV was partially observed, and this was reduced by acute treatment with NH4Cl. EFV uptake by TR-iBRB2 cells was temperature-dependent and membrane potential- and pH-independent, and was significantly reduced by NH4Cl treatment during no significant effect obtained by different extracellular pH and V-ATPase inhibitor. The EFV uptake by TR-iBRB2 cells was inhibited by cationic drugs, and inhibited by verapamil in a concentration-dependent manner with an IC50 of 98.0 μM[4].

The antiarrhythmic effects of verapamil were observed before it was appreciated that it was a calcium ion-antagonist. Intravenous verapamil is highly effective in the termination of paroxysmal reciprocating atrioventricular tachycardia, whether associated with preexcitation or involving the atrioventricular node alone. It consistently slows and regularises the ventricular response in atrial fibrillation, and usually increases the degree of AV-nodal block in atrial flutter though it occasionally induces a return to sinus rhythm. Given orally it is useful for the prophylaxis of atrioventricular reentry tachycardia, and also in modulating the atrioventricular nodal response in atrial fibrillation. Favourable response in ventricular tachycardia is exceptional and then seen in specific benign varieties. Verapamil is the agent of choice for the termination of paroxysmal supraventricular tachycardia[2].

The present study was to test the hypothesis that anti-arrhythmic properties of verapamil may be accompanied by preserving connexin43 (Cx43) protein via calcium influx inhibition. In an in vivo study, myocardial ischemic arrhythmia was induced by occlusion of the left anterior descending (LAD) coronary artery for 45 min in Sprague-Dawley rats. Verapamil, a calcium channel antagonist, was injected i.v. into a femoral vein prior to ischemia. Effects of verapamil on arrhythmias induced by Bay K8644 (a calcium channel agonist) were also determined. In an ex vivo study, the isolated heart underwent an initial 10 min of baseline normal perfusion and was subjected to high calcium perfusion in the absence or presence of verapamil. Cardiac arrhythmia was measured by electrocardiogram (ECG) and Cx43 protein was determined by immunohistochemistry and western blotting. Administration of verapamil prior to myocardial ischemia significantly reduced the incidence of ventricular arrhythmias and total arrhythmia scores, with the reductions in heat rate, mean arterial pressure and left ventricular systolic pressure. Verapamil also inhibited arrhythmias induced by Bay K8644 and high calcium perfusion. Effect of verapamil on ischemic arrhythmia scores was abolished by heptanol, a Cx43 protein uncoupler and Gap 26, a Cx43 channels inhibitor. Immunohistochemistry data showed that ischemia-induced redistribution and reduced immunostaining of Cx43 were prevented by verapamil. In addition, diminished expression of Cx43 protein determined by western blotting was observed following myocardial ischemia in vivo or following high calcium perfusion ex vivo and was preserved after verapamil administration. Our data suggest that verapamil may confer an anti-arrhythmic effect via calcium influx inhibition, inhibition of oxygen consumption and accompanied by preservation of Cx43 protein[5].

[1]. Gowarty JL, et al. Verapamil as a culprit of palbociclib toxicity. J Oncol Pharm Pract. 2019 Apr;25(3):743-746.
[2]. Krikler DM. Verapamil in arrhythmia. Br J Clin Pharmacol. 1986;21 Suppl 2:183S-189S.
[3]. Rehnqvist N,et al. Effects of metoprolol vs verapamil in patients with stable angina pectoris. The Angina Prognosis Study in Stockholm (APSIS). Eur Heart J. 1996 Jan;17(1):76-81.
[4]. Kubo Y, et al. Blood-to-Retina Transport of Fluorescence-Labeled Verapamil at the Blood-Retinal Barrier. Pharm Res. 2018 Mar 12;35(5):93.
[5]. Zhou P, et al. Anti-arrhythmic effect of Verapamil is accompanied by preservation of cx43 protein in rat heart. PLoS One. 2013 Aug 12;8(8):e71567.

2-(3,4-dimethoxyphenyl)-5-{[2-(3,4-dimethoxyphenyl)ethyl](methyl)amino}-2-(propan-2-yl)pentanenitrile is a tertiary amino compound that is 3,4-dimethoxyphenylethylamine in which the hydrogens attached to the nitrogen are replaced by a methyl group and a 4-cyano-4-(3,4-dimethoxyphenyl)-5-methylhexyl group. It is a tertiary amino compound, an aromatic ether, a polyether and a nitrile.
Verapamil is a phenylalkylamine calcium channel blocker used in the treatment of high blood pressure, heart arrhythmias, and angina, and was the first calcium channel antagonist to be introduced into therapy in the early 1960s. It is a member of the non-dihydropyridine class of calcium channel blockers, which includes drugs like [diltiazem] and [flunarizine], but is chemically unrelated to other cardioactive medications. Verapamil is administered as a racemic mixture containing equal amounts of the S- and R-enantiomer, each of which is pharmacologically distinct - the S-enantiomer carries approximately 20-fold greater potency than the R-enantiomer, but is metabolized at a higher rate.
Verapamil is a Calcium Channel Blocker. The mechanism of action of verapamil is as a Calcium Channel Antagonist, and Cytochrome P450 3A4 Inhibitor, and Cytochrome P450 3A Inhibitor, and P-Glycoprotein Inhibitor.
Verapamil is a first generation calcium channel blocker used for treatment of hypertension, angina pectoris and superventricular tachyarrhythmias. Verapamil has been linked to a low rate of serum enzyme elevations during therapy and to rare instances of clinically apparent acute liver injury.

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Verapamil is a natural product found in Teichospora striata and Schisandra chinensis with data available. LOTUS - the natural products occurrence database Verapamil is a phenylalkylamine calcium channel blocking agent. Verapamil inhibits the transmembrane influx of extracellular calcium ions into myocardial and vascular smooth muscle cells, causing dilatation of the main coronary and systemic arteries and decreasing myocardial contractility. This agent also inhibits the drug efflux pump P-glycoprotein which is overexpressed in some multi-drug resistant tumors and may improve the efficacy of some antineoplastic agents. (NCI04)
Verapamil is only found in individuals that have used or taken this drug. Verapamil is a calcium channel blocker that is a class IV anti-arrhythmia agent. [PubChem]Verapamil inhibits voltage-dependent calcium channels. Specifically, its effect on L-type calcium channels in the heart causes a reduction in ionotropy and chronotropy, thuis reducing heart rate and blood pressure. Verapamil's mechanism of effect in cluster headache is thought to be linked to its calcium-channel blocker effect, but which channel subtypes are involved is presently not known. [PubChem] Calcium channel antagonists can be quite toxic. In the management of poisoning, early recognition is critical. Calcium channel antagonists are frequently prescribed, and the potential for serious morbidity and mortality with over dosage is significant. Ingestion of these agents should be suspected in any patient who presents in an overdose situation with unexplained hypotension and conduction abnormalities. The potential for toxicity should be noted in patients with underlying hepatic or renal dysfunction who are receiving therapeutic doses. (A7844). A7844: Hofer CA, Smith JK, Tenholder MF: Verapamil intoxication: a literature review of overdoses and discussion of therapeutic options. Am J Med. 1993 Oct;95(4):431-8. PMID:8213877
A calcium channel blocker that is a class IV anti-arrhythmia agent.

C27H38N2O4

454.61

454.2832

C, 71.34; H, 8.43; N, 6.16; O, 14.08

52-53-9

Verapamil hydrochloride;152-11-4; 38321-02-7 (dexverapamil)

2520

Typically exists as colorless to light yellow ointment at room temperature

1.1±0.1 g/cm3

586.2±50.0 °C at 760 mmHg

25°C

308.3±30.1 °C

0.0±1.6 mmHg at 25°C

1.526

3.9

63.95

CC(C)C(CCCN(C)CCC1=CC(=C(C=C1)OC)OC)(C#N)C2=CC(=C(C=C2)OC)OC

SGTNSNPWRIOYBX-UHFFFAOYSA-N

InChI=1S/C27H38N2O4/c1-20(2)27(19-28,22-10-12-24(31-5)26(18-22)33-7)14-8-15-29(3)16-13-21-9-11-23(30-4)25(17-21)32-6/h9-12,17-18,20H,8,13-16H2,1-7H3

2-(3,4-dimethoxyphenyl)-5-[2-(3,4-dimethoxyphenyl)ethyl-methylamino]-2-propan-2-ylpentanenitrile

NSC-135784; NSC 135784; VERAPAMIL; 52-53-9; Iproveratril; Dilacoran; Vasolan; Isoptimo; Isoptin; Verapamilo; Verapamil

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~100 mg/mL (~219.97 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (5.50 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (5.50 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (5.50 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)