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Haider A, Xiao Z, Xia X, Chen J, Van RS, Kuang S, Zhao C, Rong J, Shao T, Ramesh P, Aravind A, Shao Y, Ran C, Young LJ, Liang SH. Development of a triazolobenzodiazepine-based PET probe for subtype-selective vasopressin 1A receptor imaging. Pharmacol Res 2021; 173:105886. [PMID: 34536549 PMCID: PMC8581590 DOI: 10.1016/j.phrs.2021.105886] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 09/09/2021] [Accepted: 09/10/2021] [Indexed: 11/21/2022]
Abstract
OBJECTIVES To enable non-invasive real-time quantification of vasopressin 1A (V1A) receptors in peripheral organs, we sought to develop a suitable PET probe that would allow specific and selective V1A receptor imaging in vitro and in vivo. METHODS We synthesized a high-affinity and -selectivity ligand, designated compound 17. The target structure was labeled with carbon-11 and tested for its utility as a V1A-targeted PET tracer by cell uptake studies, autoradiography, in vivo PET imaging and ex vivo biodistribution experiments. RESULTS Compound 17 (PF-184563) and the respective precursor for radiolabeling were synthesized in an overall yield of 49% (over 7 steps) and 40% (over 8 steps), respectively. An inhibitory constant of 0.9 nM towards the V1A receptors was measured, while excellent selectivity over the related V1B, V2 and OT receptor (IC50 >10,000 nM) were obtained. Cell uptake studies revealed considerable V1A binding, which was significantly reduced in the presence of V1A antagonists. Conversely, there was no significant blockade in the presence of V1B and V2 antagonists. In vitro autoradiography and PET imaging studies in rodents indicated specific tracer binding mainly in the liver. Further, the pancreas, spleen and the heart exhibited specific binding of [11C]17 ([11C]PF-184563) by ex vivo biodistribution experiments. CONCLUSION We have developed the first V1A-targeted PET ligand that is suitable for subtype-selective receptor imaging in peripheral organs including the liver, heart, pancreas and spleen. Our findings suggest that [11C]PF-184563 can be a valuable tool to study the role of V1A receptors in liver diseases, as well as in cardiovascular pathologies.
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Affiliation(s)
- Ahmed Haider
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, United States
| | - Zhiwei Xiao
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, United States
| | - Xiaotian Xia
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, United States; Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Jiahui Chen
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, United States
| | - Richard S Van
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019, United States
| | - Shi Kuang
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, United States
| | - Chunyu Zhao
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, United States
| | - Jian Rong
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, United States
| | - Tuo Shao
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, United States
| | | | | | - Yihan Shao
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019, United States
| | - Chongzhao Ran
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, United States
| | - Larry J Young
- Silvio O. Conte Center for Oxytocin and Social Cognition, Center for Translational Social Neuroscience, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States; Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, United Stated
| | - Steven H Liang
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, United States.
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Contreras-Romo MC, Martínez-Archundia M, Deeb O, Ślusarz MJ, Ramírez-Salinas G, Garduño-Juárez R, Quintanar-Stephano A, Ramírez-Galicia G, Correa-Basurto J. Exploring the Ligand Recognition Properties of the Human Vasopressin V1a Receptor Using QSAR and Molecular Modeling Studies. Chem Biol Drug Des 2013; 83:207-23. [DOI: 10.1111/cbdd.12229] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 07/08/2013] [Accepted: 08/12/2013] [Indexed: 11/28/2022]
Affiliation(s)
- Martha C. Contreras-Romo
- Departamento de Fisiología y Farmacología; Centro de Ciencias Básicas; Universidad Autónoma de Aguascalientes; Av. Universidad 940 20131 Aguascalientes México
| | - Marlet Martínez-Archundia
- Laboratorio de Modelado Molecular y Bioinformática; Sección de Estudios de Posgrado e Investigación de la Escuela Superior de Medicina; Instituto Politécnico Nacional; Plan de San Luis y Díaz Mirón, Del. Miguel Hidalgo 11340 México City México
| | - Omar Deeb
- Faculty of Pharmacy; Al-Quds University; Jerusalem Palestine
| | | | - Gema Ramírez-Salinas
- Laboratorio de Modelado Molecular y Bioinformática; Sección de Estudios de Posgrado e Investigación de la Escuela Superior de Medicina; Instituto Politécnico Nacional; Plan de San Luis y Díaz Mirón, Del. Miguel Hidalgo 11340 México City México
| | - Ramón Garduño-Juárez
- Instituto de Ciencias Físicas; Universidad Nacional Autónoma de México; Cuernavaca Morelos 62210 México
| | - Andrés Quintanar-Stephano
- Departamento de Fisiología y Farmacología; Centro de Ciencias Básicas; Universidad Autónoma de Aguascalientes; Av. Universidad 940 20131 Aguascalientes México
| | - Guillermo Ramírez-Galicia
- División de Estudios de Posgrado; Universidad del Papaloapan; Circuito Central 200 Parque Industrial 68301 Tuxtepec Oaxaca México
| | - José Correa-Basurto
- Laboratorio de Modelado Molecular y Bioinformática; Sección de Estudios de Posgrado e Investigación de la Escuela Superior de Medicina; Instituto Politécnico Nacional; Plan de San Luis y Díaz Mirón, Del. Miguel Hidalgo 11340 México City México
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Boto A, Hernández D, Hernández R. Efficient Conversion of Carbohydrates into 1-C-Alditols: Application to the Synthesis of Chiral γ-Substituted Butenolides and Bicyclic Alkaloid Analogues. J Org Chem 2008; 73:5287-97. [DOI: 10.1021/jo800478a] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alicia Boto
- Instituto de Productos Naturales y Agrobiología del CSIC, Avda. Astrofísico Francisco Sánchez 3, 38206-La Laguna, Tenerife, Spain
| | - Dácil Hernández
- Instituto de Productos Naturales y Agrobiología del CSIC, Avda. Astrofísico Francisco Sánchez 3, 38206-La Laguna, Tenerife, Spain
| | - Rosendo Hernández
- Instituto de Productos Naturales y Agrobiología del CSIC, Avda. Astrofísico Francisco Sánchez 3, 38206-La Laguna, Tenerife, Spain
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Tahara A, Tsukada J, Tomura Y, Suzuki T, Yatsu T, Shibasaki M. Effect of YM218, a nonpeptide vasopressin V1A receptor-selective antagonist, on rat mesangial cell hyperplasia and hypertrophy. Vascul Pharmacol 2007; 46:463-9. [PMID: 17395547 DOI: 10.1016/j.vph.2007.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Revised: 02/15/2007] [Accepted: 02/21/2007] [Indexed: 11/23/2022]
Abstract
Mesangial cell growth constitutes a key feature of progressive glomerular injury. Vasopressin (AVP), a potent peptide vasoconstrictor, acts on mesangial cells through the V(1A) receptors, inducing contraction and cell proliferation. This study examined the effects of YM218, a nonpeptide AVP V(1A) receptor-selective antagonist, on the mitogenic and hypertrophic effects of AVP in rat mesangial cells. When added to mesangial cells whose growth was arrested, AVP concentration-dependently induced hyperplasia and hypertrophy. YM218 potently prevented AVP-induced hyperplasia and hypertrophy of these cells. Furthermore, AVP stimulated endothelin (ET)-1 secretion from mesangial cells in a concentration-dependent manner and this effect was potently inhibited by YM218. ET-1 also induced hyperplasia and hypertrophy in mesangial cells and this effect was completely abolished by ET(A) receptor-selective antagonist YM598. In addition, AVP-induced hyperplasia and hypertrophy were partly inhibited by YM598. These results suggest that AVP may modulate mesangial cell growth not only by its direct action but also through the stimulation of ET-1 secretion. YM218 displays high potency in inhibiting the AVP-induced physiologic responses of mesangial cells via the V(1A) receptors and is a potent pharmacologic probe for investigating the physiologic and pathophysiologic roles of AVP in several renal diseases.
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Affiliation(s)
- Atsuo Tahara
- Institute for Drug Discovery Research, Astellas Pharma Inc., 5-2-3, Toukoudai, Tsukuba, Ibaraki 300-2698, Japan.
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Martín-Llahí M, Guevara M, Ginès P. Hyponatremia in cirrhosis: clinical features and management. ACTA ACUST UNITED AC 2006; 30:1144-51. [PMID: 17075468 DOI: 10.1016/s0399-8320(06)73492-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The presence of dilutional hyponatremia has a poor prognosis for survival in patients with cirrhosis and ascites. Effective and safe treatments are needed to improve prognosis in patients with cirrhosis and dilutional hyponatremia. The initial approach to management includes fluid restriction, low sodium diet, and minimizing the use of diuretics. In addition, the use of hypertonic saline should be avoided in patients with cirrhosis and dilutional hyponatremia. Furthermore, patients should be placed on the top of the list for liver transplantation if they are appropriate candidates. Although V2 arginine vasopressin receptor antagonists that selectively enhance solute-free water excretion in patients with cirrhosis seem very promising, two points must be considered in relation to the available data. First, although the results of phase-2 studies are encouraging, the efficacy and safety of these compounds should be further evaluated. Second, the clinical utility of these agents in cirrhosis has only been assessed in short-term studies. The long-term effects of these drugs remain unknown. Future research with these compounds should not only focus on the effects on serum sodium, but also on treatment and prevention of recurrence of ascites. In addition, the possible beneficial effects of these drugs in the prevention of hepatic encephalopathy would be worth studying.
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Moffett BS, Chang AC. Future pharmacologic agents for treatment of heart failure in children. Pediatr Cardiol 2006; 27:533-51. [PMID: 16933064 DOI: 10.1007/s00246-006-1289-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Accepted: 04/27/2006] [Indexed: 11/26/2022]
Abstract
The addition of new agents to the armamentarium of treatment options for heart failure in pediatric patients is exciting and challenging. Administration of these therapies to pediatric patients will require careful scrutiny of the data and skilled application. Developmental changes in drug metabolism, excretion, and distribution are concerning in pediatric patients, and inappropriate evaluation of these parameters can have disastrous results. Manipulation of the neurohormonal pathways in heart failure has been the target of most recently developed pharmacologic agents. Angiotensin receptor blockers (ARBs), aldosterone antagonists, beta-blockers, and natriuretic peptides are seeing increased use in pediatrics. In particular, calcium sensitizing agents represent a new frontier in the treatment of acute decompensated heart failure and may replace traditional inotropic therapies. Endothelin receptor antagonists have shown benefit in the treatment of pulmonary hypertension, but their use in heart failure is still debatable. Vasopressin antagonists, tumor necrosis factor inhibitors, and neutral endopeptidase inhibitors are also targeting aspects of the neurohormonal cascade that are currently not completely understood. The future of pharmacologic therapies will include pharmacogenomic studies on new and preexisting therapies for pediatric heart failure. The education and skill of the practitioner when applying these agents in pediatric heart failure is of utmost importance.
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Affiliation(s)
- Brady S Moffett
- Department of Pharmacy, Texas Children's Hospital, 6621 Fannin Street, MC 2-2510, Houston, TX 77030, USA.
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Tahara A, Tsukada J, Tomura Y, Momose K, Suzuki T, Yatsu T, Shibasaki M. Effects of YM218, a nonpeptide vasopressin V1A receptor-selective antagonist, on vasopressin-induced growth responses in human mesangial cells. Eur J Pharmacol 2006; 538:32-8. [PMID: 16678155 DOI: 10.1016/j.ejphar.2006.03.055] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2006] [Revised: 03/21/2006] [Accepted: 03/27/2006] [Indexed: 11/26/2022]
Abstract
Mesangial cells are centrally-located glomerular pericytes with contractile, endocrine, and immunity-regulating functions. These cells are thought to maintain normal glomerular function, since mesangial cell proliferation and extracellular matrix formation are hallmarks of chronic glomerular disease. Vasopressin causes mesangial cell contraction, proliferation and hypertrophy. Consequently, the effects of YM218, a potent, nonpeptide vasopressin V(1A) receptor-selective antagonist, on the growth responses of human mesangial cells to vasopressin were investigated. YM218 showed high affinity for vasopressin V(1A) receptors, exhibiting a K(i) value of 0.18 nM. Vasopressin concentration-dependently increased intracellular Ca(2+) levels and induced hyperplasia and hypertrophy in cultured mesangial cells, YM218 potently inhibited these vasopressin-induced responses. These results clearly show that YM218 has both strong affinity for human mesangial cell vasopressin V(1A) receptors and great potency in inhibiting the vasopressin-induced growth responses of mesangial cells controlled by the vasopressin V(1A) receptors. The hyperplasia and hypertrophy of mesangial cells in vitro caused by vasopressin indicate its possible in vivo role in glomerular disease pathogenesis. Therefore, YM218 is a potent pharmacologic probe to investigate the physiologic and pathophysiologic roles of vasopressin in the development of renal disease.
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Affiliation(s)
- Atsuo Tahara
- Institute for Drug Discovery Research, Astellas Pharma Inc., 5-2-3 Toukoudai, Tsukuba, Ibaraki 300-2698, Japan.
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Galanski ME, Erker T, Studenik CR, Kamyar M, Rawnduzi P, Pabstova M, Lemmens-Gruber R. Synthesis and pharmacological profile of non-peptide vasopressin antagonists. Eur J Pharm Sci 2005; 24:421-31. [PMID: 15784332 DOI: 10.1016/j.ejps.2004.12.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2004] [Revised: 11/24/2004] [Accepted: 12/16/2004] [Indexed: 11/18/2022]
Abstract
Recently we presented a series of 6-ethyl and 6-benzylthieno[2,3-b][1,4]thiazine derivatives with relaxing effects on vascular smooth muscle and terminal ileum. In this report the synthesis of further thieno[2,3-b][1,4]thiazine derivatives and related compounds with a thieno[2,3-b][1,4]thiazepine or thieno[3,2-b][1,4]thiazine ring system is described. The pharmacological effect of the agents was tested in isolated smooth (terminal ileum, pulmonary artery, aortic rings, myometrial strips) and heart (papillary muscle, spontaneously beating right atrium) muscle preparations of the guinea pig. Contractions were measured isometrically, and smooth muscle preparations were either precontracted with high K+ (60 or 90 mM KCl containing nutrient solution) or with agonists, while papillary muscles were electrically stimulated (1 Hz). The vasopressin antagonistic activity of the test compounds was tested in isolated papillary muscles in which the V1A-receptor subtype is located. The biphasic response to vasopressin was antagonized, dependent on the chemical structure of the test compound. Thieno[3,2-b][1,4]thiazines were more potent than thieno[2,3-b][1,4]thiazine and thieno[2,3-b][1,4]thiazepine compounds. In addition, substitution of a methyl substituted terminal benzyl ring instead of a phenyl- or dichlorobenzoyl moiety attenuated the vasopressin antagonistic effect.
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Affiliation(s)
- Maria E Galanski
- Department of Medicinal/Pharmaceutical Chemistry, University of Vienna, A-1090 Vienna, Althanstrasse 14, Austria
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Tsukada J, Tahara A, Tomura Y, Kusayama T, Wada KI, Ishii N, Taniguchi N, Suzuki T, Yatsu T, Uchida W, Shibasaki M. Pharmacologic properties of YM218, a novel, potent, nonpeptide vasopressin V1A receptor-selective antagonist. Vascul Pharmacol 2005; 42:47-55. [PMID: 15722249 DOI: 10.1016/j.vph.2005.01.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2004] [Revised: 09/19/2004] [Accepted: 01/05/2005] [Indexed: 11/16/2022]
Abstract
The pharmacologic profile of YM218, (Z)-4'-{4,4-difluoro-5-[2-oxo-2-(4-piperidinopiperidino)ethylidene]-2,3,4,5-tetrahydro-1H-1-benzoazepine-1-carbonyl}-2-methyl-3-furanilide hemifumarate, a newly synthesized, nonpeptide vasopressin (AVP) receptor antagonist, was investigated using several in vitro and in vivo methods. YM218 exhibited high affinity for V1A receptors isolated from rat liver, with a Ki value of 0.50 nM. In contrast, YM218 exhibited much lower affinity for rat pituitary V1B, kidney V2, and uterus oxytocin receptors, with Ki values of 1510 nM, 72.2 nM, and 150 nM, respectively. In vivo studies revealed that YM218 dose-dependently inhibited pressor response to exogenous AVP in pithed rats (intravenous) and in conscious normotensive rats (intravenous or oral) with a long duration of action (>8 h at 3 mg/kg, p.o.). In contrast, oral administration of YM218 did not increase urine excretion in conscious rats. These results demonstrate that YM218 is a potent nonpeptide AVP V1A receptor-selective antagonist that will be useful in future studies to help clarify the physiologic and pathophysiologic roles of AVP.
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Affiliation(s)
- Junko Tsukada
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd., 21 Miyukigaoka, Tsukuba, Ibaraki 305-8585, Japan
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Tahara A, Tsukada J, Tomura Y, Wada KI, Kusayama T, Ishii N, Yatsu T, Uchida W, Taniguchi N, Tanaka A. Alterations of renal vasopressin V1A and V2 receptors in spontaneously hypertensive rats. Pharmacology 2003; 67:106-12. [PMID: 12566855 DOI: 10.1159/000067743] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2002] [Accepted: 07/25/2002] [Indexed: 11/19/2022]
Abstract
To elucidate the role of arginine vasopressin (AVP) in a hypertensive state, the characteristics of renal cortex V(1A) and medulla V(2) receptors in young spontaneously hypertensive rats (SHR) during the developmental phase of hypertension were compared with those of age-matched Wistar-Kyoto (WKY) rats using the radioligand receptor assay technique. The systolic blood pressure of 8-week-old SHR was statistically significantly higher than that of WKY rats (142 +/- 1 vs. 125 +/- 2 mm Hg). The plasma AVP levels were also significantly higher in SHR than in WKY rats (3.20 +/- 0.41 vs. 1.96 +/- 0.34 pg/ml). In SHR, the maximum capacity of (3)H-d(CH(2))(5)Tyr(Me)AVP binding to cortical V(1A) receptors (B(max)) was statistically significantly higher than that of WKY rats (39.7 +/- 2.7 vs. 22.4 +/- 0.9 fmol/mg protein). Furthermore, the B(max) values of (3)H-AVP binding to medullary V(2) receptors in SHR were also significantly higher than in WKY rats (40.2 +/- 1.9 vs. 28.3 +/- 1.3 fmol/mg protein). However, the apparent dissociation constant (K(d)) values of renal cortex V(1A) and medulla V(2) receptors in SHR and WKY rats were not significantly different. These results indicate that increased amounts of renal cortex V(1A) and medulla V(2) receptors in SHR play an important role in the pathophysiology of hypertension.
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Affiliation(s)
- Atsuo Tahara
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical, Tsukuba, Japan.
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Tahara A, Tsukada J, Tomura Y, Kusayama T, Wada KI, Ishii N, Yatsu T, Uchida W, Taniguchi N, Tanaka A. Effect of YM471, an orally active non-peptide arginine vasopressin receptor antagonist, on human vascular smooth muscle cells. J Hypertens 2002; 20:1807-14. [PMID: 12195123 DOI: 10.1097/00004872-200209000-00026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To investigate the effects of YM471, a non-peptide arginine vasopressin (AVP) V1A and V2 receptor antagonist, on the AVP-induced growth responses in human vascular smooth muscle cells (VSMCs). METHODS Binding of YM471 to V1A receptors on VSMCs was measured using [3H]AVP. Intracellular free Ca2+ concentration was measured by fura 2 fluorescence. Mitogen-activated protein (MAP) kinase activity was determined using the p42/p44 MAP kinase specific peptide and [gamma- 32P]ATP as substrates. The effect of AVP on hyperplasia and hypertrophy of VSMCs was determined by cell number and protein content measurements. RESULTS YM471 potently and concentration-dependently inhibited the specific binding of [ 3H]AVP to V1A receptors on VSMCs, exhibiting an inhibition constant (Ki ) of 0.35 nmol/l. YM471 inhibited the AVP-induced increase in intracellular free Ca concentration with an 50% inhibition concentration (IC50 ) of 2.01 nmol/l and inhibited the activation of MAP kinase with an IC50 of 6.11 nmol/l. In addition, AVP concentration-dependently induced hyperplasia and hypertrophy in VSMCs, but YM471 prevented these AVP-induced growth effects, exhibiting IC50 values of 2.31 and 0.23 nmol/l, respectively. CONCLUSIONS These results indicate that YM471 has high affinity for V receptors on, and potently inhibits AVP-induced physiologic responses of, human VSMCs.
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Affiliation(s)
- Atsuo Tahara
- Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co. Ltd, Tsukuba, Ibaraki, Japan.
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