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Mokrov GV. Linked biaromatic compounds as cardioprotective agents. Arch Pharm (Weinheim) 2021; 355:e2100428. [PMID: 34967027 DOI: 10.1002/ardp.202100428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 11/08/2022]
Abstract
Cardiovascular diseases (CVDs) are widespread in the modern world, and their number is constantly growing. For a long time, CVDs have been the leading cause of morbidity and mortality worldwide. Drugs for the treatment of CVD have been developed almost since the beginning of the 20th century, and a large number of effective cardioprotective agents of various classes have been created. Nevertheless, the need for the design and development of new safe drugs for the treatment of CVD remains. Literature data indicate that a huge number of cardioprotective agents of various generations and mechanisms correspond to a single generalized pharmacophore model containing two aromatic nuclei linked by a linear linker. In this regard, we put forward a concept for the design of a new generation of cardioprotective agents with a multitarget mechanism of action within the indicated pharmacophore model. This review is devoted to a generalization of the currently known compounds with cardioprotective properties and corresponding to the pharmacophore model of biaromatic compounds linked by a linear linker. Particular attention is paid to the history of the creation of these drugs, approaches to their design, and analysis of the structure-action relationship within each class.
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Affiliation(s)
- Grigory V Mokrov
- Department of Medicinal Chemistry, FSBI "Zakusov Institute of Pharmacology", Moscow, Russia
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Chen W, Gan L, Wang Y. Characteristics of hERG and hNav1.5 channel blockade by sulcardine sulfate, a novel anti-arrhythmic compound. Eur J Pharmacol 2019; 844:130-138. [PMID: 30529471 DOI: 10.1016/j.ejphar.2018.12.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Revised: 11/29/2018] [Accepted: 12/05/2018] [Indexed: 11/30/2022]
Abstract
Sulcardine sulfate (sulcardine) is a novel anti-arrhythmic compound, which blocks multiple channels and was shown to be safe and tolerated in clinical trials. The aim of the present study was to investigate the electrophysiological characteristics of sulcardine on the hERG and hNav1.5 channels. The hERG and hNav1.5 channels were heterologously stably expressed in human embryonic kidney 293 cells, and the effects of sulcardine on the hERG and hNav1.5 channels were recorded using the standard whole-cell patch-clamp technique. Sulcardine inhibited hERG channels in a concentration-dependent and reversible manner (IC50 = 94.3 μM). In addition, sulcardine shifted the activation curve of hERG channels to more negative potentials. The relative block of sulcardine on hERG channels was close to zero at the time point corresponding to channel opening, which was achieved by applying a depolarizing voltage, and quickly increased afterward. Sulcardine inhibited hNav1.5 channels in a concentration-dependent and reversible manner (IC50 = 15.0 μM) and shifted the inactivation curve of hNav1.5 channels to more negative potentials. The blockade of sulcardine on hNav1.5 channels was use-dependent. In conclusion, sulcardine is a potent hNav1.5 channel blocker with a mild inhibitory effect on hERG channels and preferentially binds to both hERG and hNav1.5 channels in the open and inactivated states rather than in the resting state.
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Affiliation(s)
- Weihai Chen
- Key Laboratory of Cognition and Personality (Southwest University), Ministry of Education; Faculty of Psychology, Southwest University, Chongqing, China; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
| | - Lu Gan
- Key Laboratory of Cognition and Personality (Southwest University), Ministry of Education; Faculty of Psychology, Southwest University, Chongqing, China
| | - Yiping Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
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Wang M, Shan J, Yang Q, Ma X, Jin S, Guo X, You Q, Tang Y. Antiarrhythmic efficacy of CPUY102122, a multiple ion channel blocker, on rabbits with ischemia/reperfusion injury. Pharmacol Rep 2014; 66:1022-30. [PMID: 25443730 DOI: 10.1016/j.pharep.2014.06.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 06/17/2014] [Accepted: 06/17/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND The antiarrhythmic potential of a novel multichannel blocker CPUY102122 (CY22) was investigated in the present study. METHODS The effect of CY22 on rapid delayed rectifier potassium channel current (IKr) was studied using whole-cell patch clamp techniques in Chinese Hamster Ovary cells stably expressing human Ether-à-go-go-Related Gene. We further evaluated the antioxidant effects of CY22 and demonstrated the reversal of connexin down-regulation in the development of cardiac ventricular arrhythmias, which was produced using coronary ligation/reperfusion in rabbits. CY22 and Amiodarone were administered 30min prior to the procedure. Next, electrocardiograms were recorded, protein expression of left ventricular Connexin43 (Cx43), non-phosphorylation-Cx43 (np-Cx43), Rac-1 and gp-91[phox] were assayed using Western blot analysis, microstructural changes in the myocardium were observed and redox system activity was assayed. RESULTS CY22 inhibited IKr in a concentration-dependent manner with IC50 value of 2.8±0.8μmol/L. CY22 treatment significantly decreased T-wave amplitude and QTc arrhythmic scores and ameliorated the shape of the infarcted myocardium compared to the model group. CY22 decreased the serum levels of creatine kinase, lactate dehydrogenase, and myocardial levels of malondialdehyde, as well as increased superoxide dismutase activity. Cx43 expression in the left ventricle was significantly increased by CY22 treatment, which significantly decreased np-43 expression, Rac-1 activity and gp-91[phox] protein expression. CONCLUSIONS These results indicated that CY22 has both antiarrhythmic and cardiovascular protective effects partly by blocking IKr, the production of antioxidants and protection of Cx43.
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Affiliation(s)
- Minhui Wang
- Department of Clinical Pharmacy, China Pharmaceutical University, Nanjing, China; Anhui Provincial Center for Drug Clinical Evaluation, Yijishan Hospital of Wannan Medical College, Wuhu, China.
| | - Jiaojiao Shan
- Department of Clinical Pharmacy, China Pharmaceutical University, Nanjing, China.
| | - Qian Yang
- Department of Medicinal Chemistry, China Pharmaceutical University, Nanjing, China.
| | - Xianglei Ma
- Department of Clinical Pharmacy, China Pharmaceutical University, Nanjing, China.
| | - Sisi Jin
- Department of Clinical Pharmacy, China Pharmaceutical University, Nanjing, China.
| | - Xiaoke Guo
- Department of Medicinal Chemistry, China Pharmaceutical University, Nanjing, China.
| | - Qidong You
- Department of Medicinal Chemistry, China Pharmaceutical University, Nanjing, China.
| | - Yiqun Tang
- Department of Clinical Pharmacy, China Pharmaceutical University, Nanjing, China.
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Zemzemi N, Rodriguez B. Effects of L-type calcium channel and human ether-a-go-go related gene blockers on the electrical activity of the human heart: a simulation study. Europace 2014; 17:326-33. [PMID: 25228500 PMCID: PMC4309991 DOI: 10.1093/europace/euu122] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Aims Class III and IV drugs affect cardiac human ether-a-go-go related gene (IKr) and L-type calcium (ICaL) channels, resulting in complex alterations in repolarization with both anti- and pro-arrhythmic consequences. Interpretation of their effects on cellular and electrocardiogram (ECG)-based biomarkers for risk stratification is challenging. As pharmaceutical compounds often exhibit multiple ion channel effects, our goal is to investigate the simultaneous effect of ICaL and IKr block on human ventricular electrophysiology from ionic to ECG level. Methods and results Simulations are conducted using a human body torso bidomain model, which includes realistic representation of human membrane kinetics, anatomy, and fibre orientation. A simple block pore model is incorporated to simulate drug-induced ICaL and IKr blocks, for drug dose = 0, IC50, 2× IC50, 10× IC50, and 30× IC50. Drug effects on human ventricular activity are quantified for different degrees and combinations of ICaL and IKr blocks from the ionic to the body surface ECG level. Electrocardiogram simulations show that ICaL block results in shortening of the QT interval, ST elevation, and reduced T-wave amplitude, caused by reduction in action potential duration and action potential amplitude during the plateau phase, and in repolarization times. In contrast, IKr block results in QT prolongation and reduced T-wave amplitude. When ICaL and IKr blocks are combined, the degree of ICaL block strongly determines QT interval whereas the effect of IKr block is more pronounced on the T-wave amplitude. Conclusion Our simulation study provides new insights into the combined effect of ICaL and IKr blocks on human ventricular activity using a multiscale computational human torso model.
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Affiliation(s)
- Nejib Zemzemi
- Carmen team, INRIA Bordeaux Sud-Ouest, 200 avenue de la vieille tour, Talence Cedex 33405, France
| | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Oxford OX1 3QD, UK
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Xu J, Yu P, Yang Q, Meng JN, Shan JJ, You QD, Tang YQ. Antiarrhythmic Efficacy of CPUY11018 Under Pathological Conditions. Drug Dev Res 2013. [DOI: 10.1002/ddr.21060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Jing Xu
- Research Division of Pharmacology; China Pharmaceutical University; Nanjing; China
| | - Peng Yu
- Research Division of Pharmacology; China Pharmaceutical University; Nanjing; China
| | - Qian Yang
- Department of Medicinal Chemistry; China Pharmaceutical University; Nanjing; China
| | - Jia-ning Meng
- Research Division of Pharmacology; China Pharmaceutical University; Nanjing; China
| | - Jiao-jiao Shan
- Research Division of Pharmacology; China Pharmaceutical University; Nanjing; China
| | - Qi-dong You
- Department of Medicinal Chemistry; China Pharmaceutical University; Nanjing; China
| | - Yi-qun Tang
- Research Division of Pharmacology; China Pharmaceutical University; Nanjing; China
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Raisanberine protected pulmonary arterial rings and cardiac myocytes of rats against hypoxia injury by suppressing NADPH oxidase and calcium influx. Acta Pharmacol Sin 2012; 33:625-34. [PMID: 22555370 DOI: 10.1038/aps.2012.7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
AIM To investigate the protection of pulmonary arterial rings and cardiac myocytes of rats by raisanberine (RS), a derivative of berberine, against hypoxia injury and to elucidate the action mechanisms. METHODS Adult SD rats were exposed to intermittent hypoxia for 17 d or 28 d. The pulmonary arterial rings were isolated and vascular activity was measured using a transducer and computer-aided system. The difference in the tension produced by phenylephrine in the presence and absence of L-nitroarginine (10 μmol/L) was referred to as the NO bioavailability; the maximum release of NO was assessed by the ratio of the maximal dilatation caused by ACh to those caused by sodium nitroprusside. After the lungs were fixed, the internal and the external diameters of the pulmonary arterioles were measured using a graphic analysis system. Cultured cardiac myocytes from neonatal rats were exposed to H(2)O(2) (10 μmol/L) to mimic hypoxia injury. ROS generation and [Ca(2+)](i) level in the myocytes were measured using DHE and Fluo-3 fluorescence, respectively. RESULTS Oral administration of RS (80 mg/kg), the NADPH oxidase inhibitor apocynin (APO, 80 mg/kg) or Ca(2+) channel blocker nifedipine (Nif, 10 mg/kg,) significantly alleviated the abnormal increase in the vasoconstriction force and endothelium-related vasodilatation induced by the intermittent hypoxia. The intermittent hypoxia markedly decreased the NO bioavailability and maximal NO release from pulmonary arterial rings, which were reversed by APO or RS administration. However, RS administration did not affect the NO bioavailability and maximal NO release from pulmonary arterial rings of normal rats. RS, Nif or APO administration significantly attenuated the pulmonary arteriole remodeling. Treatment of cultured cardiac myocytes with RS (10 μmol/L) suppressed the ROS generation and [Ca(2+)](i) increase induced by H(2)O(2), which were comparable to those caused by APO (10 μmol/L) or Nif (0.1 μmol/L). CONCLUSION Raisanberine relieved hypoxic/oxidant insults to the pulmonary artery and cardiac myocytes of rats by suppressing activated NADPH oxidase and increased calcium influx.
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Guo X, Chen CL, Yang Q, Yin YM, You QD, Tang YQ. Effects of a novel class III antiarrhythmic agent, CPUY11018, on rat atrial fibrillation. Drug Dev Res 2010. [DOI: 10.1002/ddr.20375] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Li N, Jia N, Dai DZ, Hu C, Dai Y. Role of endothelin in the effects of isoprenaline on potassium currents and calsequestrin 2 expression in the heart. Clin Exp Pharmacol Physiol 2010. [DOI: 10.1111/j.1440-1681.2010.05349.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Liu QN, Zhang L, Gong PL, Yang XY, Zeng FD. Inhibitory effects of dauricine on early afterdepolarizations and L-type calcium current. Can J Physiol Pharmacol 2010; 87:954-62. [PMID: 19935903 DOI: 10.1139/y09-090] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have previously reported that dauricine exerted antiarrhythmic effects on various experimental arrhythmias. To further clarify its mechanism, the effects of dauricine on action potential duration (APD), early afterdepolarizations (EADs), triangulation, which is defined as the repolarization time from APD at 30% level (APD30) to APD at 90% level (APD90), and L-type calcium current (I(Ca-L)) were studied using standard microelectrode techniques on rabbit papillary muscles and whole-cell patch clamp techniques on single myocytes isolated from rabbits by enzymatic digestion, respectively. Cardiac hypertrophy was induced by coarctating the abdominal aorta of rabbits. The results showed that in papillary muscles of hypertrophied rabbits, 1 micromol/L dofetilide, a selective IKr blocker, prolonged APD50 and APD90 and induced EADs (4/6, p < 0.01) with hypokalemia ([K+]o = 2.7 mmol/L). Dauricine inhibited EADs (p < 0.01) and shortened the prolonged APD (p < 0.01). In single myocytes, dauricine also inhibited EADs induced by dofetilide, hypokalemia, and hypomagnesaemia. Dauricine decreased the triangulation and reduced the peak amplitude of I(Ca-L) at all potentials tested. Dauricine shifted the steady-state activation curves to the right and steady-state inactivation curves to the left and prolonged the tau value of the recovery curve. These results suggest that dauricine inhibits EADs and this effect may be associated with its blockade of I(Ca-L).
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Affiliation(s)
- Qiang-Ni Liu
- Department of Pharmacology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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Qi MY, Feng Y, Dai DZ, Li N, Cheng YS, Dai Y. CPU86017, a berberine derivative, attenuates cardiac failure through normalizing calcium leakage and downregulated phospholamban and exerting antioxidant activity. Acta Pharmacol Sin 2010; 31:165-74. [PMID: 20139899 DOI: 10.1038/aps.2009.180] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
AIM To investigate whether CPU86017, a berberine derivative, attenuates heart failure by blocking calcium influx and exerting its antioxidant activity. METHODS Myocardial infarction was induced in male Sprague-Dawley rats for 17 d followed by isoproterenol (ISO) (5 mg/kg, sc) treatment for 5 d to reduce cardiac function. The rats were divided into 5 groups: sham operation, myocardial infarction (MI), MI plus ISO, and co-treated (in mg/kg, po) with either propranolol (PRO, 10) or CPU86017 (80). Hemodynamic measurements were conducted, and measurements of the redox system, calcium handling proteins and endothelin (ET) system in vivo were done. Furthermore, calcium flux studies and PLB immunocytochemistry were conducted in vitro. RESULTS Compared to sham operation, HF was evident following MI and further worsened by ISO treatment. This occurred in parallel with downregulated mRNA and protein production of SERCA2a, PLB, and FKBP12.6, and was associated with upregulation of preproET-1, endothelin converting enzyme, and PKA mRNA production in the myocardium in vivo. Calcium leakage was induced by ISO treatment of isolated beating myocytes in vitro. These changes were attenuated by treatment with either PRO or CPU86017. PLB fluorescence in myocytes was downregulated by ISO treatment, and was relieved significantly by treatment with antioxidant aminoguanidine, ascorbic acid or CPU86017 in vitro. CONCLUSION HF, calcium leakage, downregulated PLB, FKBP12.6, SERCA2a production, and upregulated PKA were caused by ISO treatment, and were abolished by CPU86017 treatment. The beneficial effects of CPU86017 are attributable to its antioxidant and calcium influx blocking effects.
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Hamed KH, Hu C, Dai DZ, Yu F, Dai Y. CPU228, a derivative of dofetilide, relieves cardiac dysfunction by normalizing FKBP12.6, NADPH oxidase and protein kinase C ε in the myocardium. J Pharm Pharmacol 2010; 62:77-83. [DOI: 10.1211/jpp.62.01.0008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Abstract
Objectives
The aim of this study was to determine if CPU228, a derivative of dofetilide, is more effective than dofetilide in attenuating isoproterenol-induced heart failure by recovering downregulated FK506 binding protein (FKBP12.6), and suppressing oxidative stress, upregulated NADPH oxidase and protein kinase C ε (PKCε) hyperphosphorylation in the myocardium.
Methods
Heart failure was induced by isoproterenol (1 mg/kg s.c. for 5 days) in male Sprague-Dawley rats. Intervention with either CPU228 or dofetilide (2 mg/kg on Days 3–5) was then conducted in vivo and in vitro.
Key findings
Isoproterenol produced compromised left ventricular systolic pressure, left ventricular pressure rise (dp/dtmax) and fall (dp/dtmin), and left ventricular end-diastolic pressure, associated with oxidative stress, abnormal FKBP12.6, NADPH oxidase p67phox and PKCε in the myocardium. CPU228 was more effective in attenuating these changes than dofetilide in vivo. Dofetilide produced a prolonged QTc to replace a shortened one. In primary neonatal cardiomyocytes, cultured with isoproterenol and treated with either CPU228 or dofetilide at 10−8, 10−7 and 10−6 mol/l, isoproterenol produced a hyperadrenergic state characterized by downregulated FKBP12.6, upregulated NADPH oxidase p67phox and PKCε in vitro. CPU228 was more effective than dofetilide in recovering these changes in a dose-dependent manner without a prolonged QTc.
Conclusions
CPU228 was more effective than dofetilide in attenuating heart failure by normalizing isoproterenol-induced changes, including downregulation of FKBP12.6, upregulation of NADPH oxidase and PKCε hyperphosphorylation in vivo and in vitro.
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Affiliation(s)
- Khan Hussien Hamed
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
- Faculty of Medicine and Health Sciences, University of Aden, Yemen
| | - Chen Hu
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - De-Zai Dai
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Feng Yu
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Yin Dai
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
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Assessment of the Ion Channel-blocking Profile of the Novel Combined Ion Channel Blocker AZD1305 and Its Proarrhythmic Potential Versus Dofetilide in the Methoxamine-sensitized Rabbit In Vivo. J Cardiovasc Pharmacol 2009; 54:82-9. [DOI: 10.1097/fjc.0b013e3181ac62c9] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Luo L, Dai DZ, Dai Y. EFFECT OF THE ENDOTHELIN RECEPTOR ANTAGONIST CPU0213, AND ITS MODULATION BY RIFAMPIN, ON CARDIAC AND VASCULAR TISSUE FOLLOWING CHRONIC ISOPROTERENOL TREATMENT. Clin Exp Pharmacol Physiol 2008; 35:757-65. [DOI: 10.1111/j.1440-1681.2007.04856.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Li N, Yang L, Dai DZ, Wang QJ, Dai Y. Chiral separation of racemate CPU86017, an anti-arrhythmic agent, produces stereoisomers possessing favourable ion channel blockade and less alpha-adrenoceptor antagonism. Clin Exp Pharmacol Physiol 2007; 35:643-50. [PMID: 18177475 DOI: 10.1111/j.1440-1681.2007.04854.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
1. CPU86017 is an effective anti-arrhythmic agent of the Class III complex that has two chiral centres, 7N and 13aC. As a promising anti-arrhythmic agent, the blockade on I(Kr), I(Ks) and calcium influx may be modulated to be mild, moderate and potent, with less a-adrenoceptor blockade. In order to improve activity at ion channels, four stereoisomers, namely SS ((+)-7S,13aS-CPU86017), SR ((-)-7S,13aR-CPU86017), RR ((-)-7R,13aR-CPU86017) and RS ((+)-7R,13aS-CPU86017), have been separated. In the present study, the effects of these four isomers on I(Kr) and I(Ks), calcium channels and a-adrenoceptors were compared with the effects of the racemate CPU86017. 2. In the present study, I(Kr) and I(Ks) were measured as tail currents (I(Kr.tail) and I(Ks.tail), respectively) using the whole-cell patch-clamp technique. Antagonism of receptor-operated calcium channels and voltage-dependent calcium channels (VDC) in vascular smooth muscle by CPU86017 and the four isomers were tested as suppression of phenylephrine- or KCl-induced contractions of aortic rings, respectively. 3. For I(Kr.tail) inhibition, the IC(50) of SS, SR, RR, RS and CPU86017 was 2.86 +/- 1.20, 39.4 +/- 8.5, 3.48 +/- 0.80, 7.65 +/- 1.50 and 12.5 +/- 7.8 x 10(-9) mol/L, respectively; for I(Ks.tail) inhibition IC(50) values were 16.9 +/- 4.0, 20.0 +/- 2.1, 99.1 +/- 5.9, 160 +/- 81 and 65.0 +/- 4.7 x 10(-9) mol/L, respectively. The SR isomer showed balanced blockade of I(Kr) and I(Ks) that was associated with a loss of a-adrenoceptor antagonism but enhanced VDC blockade. 4. Configuration of 13aC critically determines I(Kr) blockade and the Ca(2+) antagonism of the isomers of CPU86017. The SR isomer exhibits mild blockade of I(Kr), moderately enhanced blockade of I(Ks) and Ca(2+) influx and less a-adrenoceptor antagonism compared with the racemate and may be promising as an anti-arrhythmic.
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Affiliation(s)
- Na Li
- Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China
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