Verapamil hydrochloride is an L-type calcium channel antagonist.

Calcium channel^[1]

Verapamil (hydrochloride) is an L-type calcium channel antagonist. The combination of Bortezomib and Verapamil (70 µM) markedly declines the viability of the JK-6L, RPMI 8226, and ARH-77 cell lines after 16 hours of culture^[1]. The enzyme hydrolase activity of recombinant human carboxylesterase (CES2) is substantially inhibited by Verapamil with K_i of 3.84±0.99μM^[2].

Verapamil, a calcium channel antagonist, is injected i.v. into a femoral vein prior to ischemia. Verapamil (1 mg/kg) significantly decreases the incidence of ventricular arrhythmias including premature ventricular contractions (PVC), ventricular tachycardia (VT) and ventricular fibrillation (VF) for 45-min coronary artery occlusion. Total arrhythmia scores are significantly increased when the heart is subjected to ischemia (P<0.01 vs.="" sham).="" verapamil="" (1="" mg/kg)="" significantly="" prevented="" the="" enhancement="" of="" total="" arrhythmia="" scores="" induced="" by="" ischemia=""><0.01 vs.="" ischemia).="" results="" indicate="" that="" verapamil="" exerts="" an="" anti-arrhythmic="">^[3].

• [1]. Meister S, et al. Calcium channel blocker Verapamil enhances endoplasmic reticulum stress and cell death induced by proteasome inhibition in myeloma cells. Neoplasia. 2010 Jul;12(7):550-61.

  [2]. Yanjiao X, et al. Evaluation of the inhibitory effects of antihypertensive drugs on human carboxylesterase in vitro. Drug Metab Pharmacokinet. 2013;28(6):468-74.

  [3]. 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.

Verapamil is dissolved in DMSO and stored, and then diluted with appropriate media before use^[1].

Cells (1×10⁵) are treated with 10 nM Bortezomib and/or 70 µM Verapamil for 16 hours and incubated for another 4 hours with Alamar-Blue. Activity of the mitochondrial dehydrogenase results in conversion of the coloring, which is followed by measurement of the absorption using a spectrophotometer^[1]. MCE has not independently confirmed the accuracy of these methods. They are for reference only.

Verapamil hydrochloride is dissolved in DMSO and then diluted with PBS or saline^[3].

Rat^[3]
Adult male Sprague-Dawley (SD) rats (250−350 g) are used. Verapamil (1 mg/kg) is injected i.v. into a femoral vein 10 min prior to ischemia. A sham group undergoes the same surgical procedures, except the suture underneath the LAD is left untied. In another series of experiment, arrhythmia is induced by Bay K8644, an L-type calcium channel agonist, at a dose of 0.1 mg/kg given i.v. into the FV. Verapamil (1 mg/kg) is administered 10 min prior to Bay K8644. All injections are performed within 30 sec. MCE has not independently confirmed the accuracy of these methods. They are for reference only.

• [1]. Meister S, et al. Calcium channel blocker Verapamil enhances endoplasmic reticulum stress and cell death induced by proteasome inhibition in myeloma cells. Neoplasia. 2010 Jul;12(7):550-61.

  [2]. Yanjiao X, et al. Evaluation of the inhibitory effects of antihypertensive drugs on human carboxylesterase in vitro. Drug Metab Pharmacokinet. 2013;28(6):468-74.

  [3]. 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.

491.06

C₂₇H₃₉ClN₂O₄

152-11-4

Room temperature in continental US; may vary elsewhere

DMSO: ≥ 31 mg/mL

* "<1 mg/ml"="" means="" slightly="" soluble="" or="" insoluble.="" "≥"="" means="" soluble,="" but="" saturation="">