1
|
Mishra SK, Choudhury S. Experimental Protocol for Cecal Ligation and Puncture Model of Polymicrobial Sepsis and Assessment of Vascular Functions in Mice. Methods Mol Biol 2018; 1717:161-187. [PMID: 29468592 DOI: 10.1007/978-1-4939-7526-6_14] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Sepsis is the systemic inflammatory response syndrome that occurs during infection and is exacerbated by the inappropriate immune response encountered by the affected individual. Despite extensive research, sepsis in humans is one of the biggest challenges for clinicians. The high mortality rate in sepsis is primarily due to hypoperfusion-induced multiorgan dysfunctions , resulting from a marked decrease in peripheral resistance. Vascular dysfunctions are further aggravated by sepsis-induced impairment in myocardial contractility. Circulatory failure in sepsis is characterized by refractory hypotension and vascular hyporeactivity (vasoplegia) to clinically used vasoconstrictors. To investigate the complex pathophysiology of sepsis and its associated multiple organ dysfunction, several animal models have been developed. However, cecal ligation and puncture (CLP) model of murine sepsis is still considered as 'gold standard' in sepsis research. In this protocol we have described the standard surgical procedure to induce polymicrobial sepsis by cecal ligation and puncture. Further, we have described the protocol to study the molecular mechanisms underlying vascular dysfunctions in sepsis.
Collapse
Affiliation(s)
- Santosh Kumar Mishra
- Division of Pharmacology & Toxicology, Indian Veterinary Research Institute, Bareilly, Uttar Pradesh, India.
- , Bhubaneswar, Odisha, India.
| | - Soumen Choudhury
- Department of Pharmacology and Toxicology, College of Veterinary Science & Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go-Anusandhan Sansthan, Mathura, Uttar Pradesh, India
| |
Collapse
|
2
|
Harris DA, Park JM, Lee KS, Xu C, Stella N, Hague C. Label-Free Dynamic Mass Redistribution Reveals Low-Density, Prosurvival α1B-Adrenergic Receptors in Human SW480 Colon Carcinoma Cells. J Pharmacol Exp Ther 2017; 361:219-228. [PMID: 28196836 DOI: 10.1124/jpet.116.237255] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 02/10/2017] [Indexed: 12/11/2022] Open
Abstract
Small molecules that target the adrenergic family of G protein-coupled receptors (GPCRs) show promising therapeutic efficacy for the treatment of various cancers. In this study, we report that human colon cancer cell line SW480 expresses low-density functional α1B-adrenergic receptors (ARs) as revealed by label-free dynamic mass redistribution (DMR) signaling technology and confirmed by quantitative reverse-transcriptase polymerase chain reaction analysis. Remarkably, although endogenous α1B-ARs are not detectable via either [3H]-prazosin-binding analysis or phosphoinositol hydrolysis assays, their activation leads to robust DMR and enhanced cell viability. We provide pharmacological evidence that stimulation of α1B-ARs enhances SW480 cell viability without affecting proliferation, whereas stimulating β-ARs diminishes both viability and proliferation of SW480 cells. Our study illustrates the power of label-free DMR technology for identifying and characterizing low-density GPCRs in cells and suggests that drugs targeting both α1B- and β-ARs may represent valuable small-molecule therapeutics for the treatment of colon cancer.
Collapse
Affiliation(s)
- Dorathy-Ann Harris
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
| | - Ji-Min Park
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
| | - Kyung-Soon Lee
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
| | - Cong Xu
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
| | - Nephi Stella
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
| | - Chris Hague
- Departments of Pharmacology (D.-A.H., J.-M.P., K.-S.L., C.X., N.S., C.H.) and Psychiatry and Behavioral Sciences (C.X., N.S.), University of Washington School of Medicine, Seattle, Washington
| |
Collapse
|
3
|
Ruegsegger GN, Toedebusch RG, Braselton JF, Childs TE, Booth FW. Left ventricle transcriptomic analysis reveals connective tissue accumulation associates with initial age-dependent decline in V̇o2peak from its lifetime apex. Physiol Genomics 2016; 49:53-66. [PMID: 27913688 DOI: 10.1152/physiolgenomics.00083.2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 11/08/2016] [Accepted: 11/28/2016] [Indexed: 12/17/2022] Open
Abstract
Peak oxygen consumption (V̇o2peak) strongly predicts morbidity and mortality better than other established risk factors, yet mechanisms associated with its age-associated decline are unknown. Our laboratory has shown that V̇o2peak first begins to decrease at the same age of 19-20 wk in both sedentary and wheel-running, female Wistar rats (Toedebusch et al., Physiol Genomics 48: 101-115, 2016). Here, we employed a total systemic approach using unsupervised interrogation of mRNA with RNA sequencing. The purpose of our study was to analyze transcriptomic profiles from both sedentary (SED) and wheel-running (RUN) conditions as a strategy to identify pathways in the left ventricle that may contribute to the initial reductions in V̇o2peak occurring between 19 and 27 wk of age. Transcriptomic comparisons were made within both SED and RUN rats between 19 and 27 wk (n = 5-8). Analysis of mRNAs shared in SED and RUN between 19 and 27 wk found 17 upregulated (e.g., Adra1d, Rpl17, Xpo7) and 8 downregulated (e.g., Cdo1, Ctfg, Sfrp1) mRNAs, at 19 wk, respectively. Furthermore, bioinformatics analysis of mRNAs common to SED and RUN produced networks suggestive of increased connective tissue development at 27 vs. 19 wk. Additionally, Ctfg mRNA was negatively associated with V̇o2peak in both SED and RUN (P < 0.05). In summary, transcriptomic analysis revealed mRNAs and networks associated with increased connective tissue development, decreased α-adrenergic activity, and decreased protein translation in the left ventricle that could, in part, potentially influence the initiation of the lifelong reduction in V̇o2peak, independent of physical activity levels.
Collapse
Affiliation(s)
| | - Ryan G Toedebusch
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri
| | - Joshua F Braselton
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri
| | - Thomas E Childs
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri
| | - Frank W Booth
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri; .,Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri.,Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri; and.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| |
Collapse
|
4
|
Kandasamy K, Choudhury S, Singh V, Addison MP, Darzi SA, Kasa JK, Thangamalai R, Dash JR, Kumar T, Sultan F, Singh TU, Parida S, Mishra SK. Erythropoietin Reverses Sepsis-Induced Vasoplegia to Norepinephrine Through Preservation of α1D-Adrenoceptor mRNA Expression and Inhibition of GRK2-Mediated Desensitization in Mouse Aorta. J Cardiovasc Pharmacol Ther 2015; 21:100-13. [DOI: 10.1177/1074248415587968] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 04/20/2015] [Indexed: 12/12/2022]
Abstract
We investigated the effect of erythropoietin (EPO) posttreatment on survival time and vascular functions in a mouse model of sepsis. Sepsis was induced by cecal ligation and puncture. After 20 ± 2 hours of sepsis, thoracic aorta was isolated for assessing its reactivity to norepinephrine (NE) and acetylcholine (ACh). We also measured the tissue nitric oxide (NO) level, inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS), G protein-coupled receptor kinase 2 (GRK2), and α1D adrenoceptor messenger RNA (mRNA)/protein expression. In septic mice, EPO moderately improved the survival time from 19.68 ± 0.75 to 34.7 ± 3.2 hours. Sepsis significantly decreased the aortic contractile response to NE along with reduced α1D mRNA and protein expression. Erythropoietin significantly preserved the α1D receptor expression and restored NE-induced contractions to control levels in septic mice. Further, it attenuated the aortic α1D receptor desensitization in sepsis which was evident from reduced GRK2 mRNA expression. Accordingly, a selective GRK2 inhibitor markedly restored the contractile responses to NE in sepsis. Erythropoietin treatment attenuated iNOS mRNA expression and iNOS-induced overproduction of NO, but improved endothelium-dependent relaxation to ACh associated with increased eNOS mRNA expression. In conclusion, EPO seems to reverse sepsis-induced vasoplegia to NE through the preservation of α1D adrenoceptor mRNA/protein expression, inhibition of GRK2-mediated desensitization, and attenuation of NO overproduction in the mouse aorta.
Collapse
Affiliation(s)
- Kannan Kandasamy
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Soumen Choudhury
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Vishakha Singh
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - M. Pule Addison
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Sazad Ahmad Darzi
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Jaya Kiran Kasa
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Ramasamy Thangamalai
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Jeevan Ranjan Dash
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Tarun Kumar
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Faheem Sultan
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Thakur Uttam Singh
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Subhashree Parida
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Santosh Kumar Mishra
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| |
Collapse
|
5
|
Choudhury S, Kannan K, Pule Addison M, Darzi SA, Singh V, Singh TU, Thangamalai R, Dash JR, Parida S, Debroy B, Paul A, Mishra SK. Combined treatment with atorvastatin and imipenem improves survival and vascular functions in mouse model of sepsis. Vascul Pharmacol 2015; 71:139-50. [PMID: 25869507 DOI: 10.1016/j.vph.2015.03.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Revised: 02/28/2015] [Accepted: 03/03/2015] [Indexed: 01/22/2023]
Abstract
We have recently reported that pre-treatment, but not the post-treatment with atorvastatin showed survival benefit and improved hemodynamic functions in cecal ligation and puncture (CLP) model of sepsis in mice. Here we examined whether combined treatment with atorvastatin and imipenem after onset of sepsis can prolong survival and improve vascular functions. At 6 and 18h after sepsis induction, treatment with atorvastatin plus imipenem, atorvastatin or imipenem alone or placebo was initiated. Ex vivo experiments were done on mouse aorta to examine the vascular reactivity to nor-adrenaline and acetylcholine and mRNA expressions of α1D AR, GRK2 and eNOS. Atorvastatin plus imipenem extended the survival time to 56.00±4.62h from 20.00±1.66h observed in CLP mice. The survival time with atorvastatin or imipenem alone was 20.50±1.89h and 27.00±4.09h, respectively. The combined treatment reversed the hyporeactivity to nor-adrenaline through preservation of α1D AR mRNA/protein expression and reversal of α1D AR desensitization mediated by GRK2/Gβγ pathway. The treatment also restored endothelium-dependent relaxation to ACh through restoration of aortic eNOS mRNA expression and NO availability. In conclusion, combined treatment with atorvastatin and imipenem exhibited survival benefit and improved vascular functions in septic mice.
Collapse
Affiliation(s)
- Soumen Choudhury
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India
| | - Kandasamy Kannan
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India
| | - M Pule Addison
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India
| | - Sazad A Darzi
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India
| | - Vishakha Singh
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India
| | - Thakur Uttam Singh
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India
| | - Ramasamy Thangamalai
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India
| | - Jeevan Ranjan Dash
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India
| | - Subhashree Parida
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India
| | - Biplab Debroy
- Division of Veterinary Pathology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India
| | - Avishek Paul
- Division of Physiology and Climatology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India
| | - Santosh Kumar Mishra
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar-243122, Bareilly, Uttar Pradesh, India.
| |
Collapse
|
6
|
Wegener JW, Loga F, Stegner D, Nieswandt B, Hofmann F. Phospholipase D1 is involved in α‐adrenergic contraction of murine vascular smooth muscle. FASEB J 2014; 28:1044-8. [DOI: 10.1096/fj.13-237925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jörg W. Wegener
- For 923, Institut für Pharmakologie and Toxikologie, Technische Universität MünchenMünchenGermany
| | - Florian Loga
- For 923, Institut für Pharmakologie and Toxikologie, Technische Universität MünchenMünchenGermany
| | - David Stegner
- Lehrstuhl für Experimentelle BiomedizinUniversitätsklinikum Würzburg and Rudolf‐Virchow‐ZentrumDeutsche Forschungsgemeinschaft (DFG) Forschungszentrum für Experimentelle BiomedizinUniversität WürzburgWürzburgGermany
| | - Bernhard Nieswandt
- Lehrstuhl für Experimentelle BiomedizinUniversitätsklinikum Würzburg and Rudolf‐Virchow‐ZentrumDeutsche Forschungsgemeinschaft (DFG) Forschungszentrum für Experimentelle BiomedizinUniversität WürzburgWürzburgGermany
| | - Franz Hofmann
- For 923, Institut für Pharmakologie and Toxikologie, Technische Universität MünchenMünchenGermany
| |
Collapse
|
7
|
Contribution of α-Adrenoceptor Stimulation by Phenylephrine to Basal Nitric Oxide Production in the Isolated Mouse Aorta. J Cardiovasc Pharmacol 2013; 61:318-23. [DOI: 10.1097/fjc.0b013e318281fa2d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
8
|
Abel PW, Jain N. α-Adrenoceptor assays. CURRENT PROTOCOLS IN PHARMACOLOGY 2012; Chapter 4:Unit 4.5. [PMID: 23258599 DOI: 10.1002/0471141755.ph0405s59] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
α-Adrenoceptors mediate responses to activation of both peripheral sympathetic nerves and central noradrenergic neurons. They also serve as autoreceptors that modulate the release of norepinephrine (NE) and other neurotransmitters. There are two major classes of α-adrenoceptors, the α(1)- and α(2). Each class is subdivided into three subtypes: α(1A), α(1B), α(1D), and α(2A), α(2B), α(2C). Described in this unit are in vitro isolated tissue methods used to study α-adrenoceptor functions and to identify novel ligands for these receptors. Detailed protocols describing use of isolated tissues to study the various α(1)- and α(2)-adrenoceptor subtypes are provided.
Collapse
Affiliation(s)
- Peter W Abel
- Department of Pharmacology, Creighton University School of Medicine, Omaha, Nebraska, USA
| | | |
Collapse
|
9
|
Martínez-Salas SG, Campos-Peralta JM, Pardo JP, Hernández-Muñoz R, Ibarra M, Tanoue A, Tsujimoto G, Villalobos-Molina R. α(1D)-Adrenoceptor regulates the vasopressor action of α(1A)-adrenoceptor in mesenteric vascular bed of α(1D)-adrenoceptor knockout mice. ACTA ACUST UNITED AC 2012; 31:64-71. [PMID: 21951586 DOI: 10.1111/j.1474-8673.2011.00468.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
1 The pressor action of the α(1A)-adrenoceptor (α(1A)-AR) agonist A61603 (N-[5-(4,5-dihydro-1H-imidazol-2-yl)-2-hydroxy-5,6,7,8-tetrahydronaphthalen-1-yl] methanesulfonamide) and the α(1)-ARs agonist phenylephrine and their blockade by selective α(1)-ARs antagonists in the isolated mesenteric vascular bed of wild-type (WT) mice and α(1D)-AR knockout (KO α(1D)-AR) mice were evaluated. 2 The apparent potency of A61603 to increase the perfusion pressure in the mesenteric vascular bed of WT and KO α(1D)-AR mice is 86 and 138 times the affinity of phenylephrine, respectively. 3 A61603 also enhanced the perfusion pressure by ≈1.7 fold in the mesenteric vascular bed of WT mice compared with KO α(1D)-AR mice. 4 Because of its high affinity, low concentrations of the α(1A)-AR selective antagonist RS100329 (5-methyl-3-[3-[4-[2-(2,2,2,-trifluoroethoxy) phenyl]-1-piperazinyl] propyl]-2,4-(1H)-pyrimidinedione) shifted the agonist concentration-response curves to the right in the mesenteric vascular bed of WT and KO α(1D)-AR mice. 5 The α(1D)-AR selective antagonist BMY7378 (8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspiro[4.5] decane-7,9-dione) did not modify the A61603 or the phenylephrine-induced pressor effect. 6 The α(1B/D)-ARs alkylating antagonist chloroethylclonidine (CEC) shifted the agonist concentration-response curves to the right and decreased the maximum phenylephrine-induced vascular contraction in KO α(1D)-AR mice when compared to WT mice; however, CEC only slightly modified the contraction induced by A61603. 7 The results indicate that the isolated mesenteric vascular bed of WT and KO α(1D)-AR mice expresses α(1A)-AR, that the pressor action of α(1A)-AR is up-regulated for α(1D)-AR in WT mice and suggest an important role of α(1B)-AR in the vascular pressure evoked by phenylephrine in KO α(1D)-AR mice.
Collapse
Affiliation(s)
- S G Martínez-Salas
- Programa de Doctorado en Ciencias Biomédicas, Universidad Nacional Autónoma de México (UNAM) Escuela Militar de Graduados de Sanidad, Universidad del Ejército y Fuerza Aérea, Mexico
| | | | | | | | | | | | | | | |
Collapse
|
10
|
Goyal R, Mittal A, Chu N, Zhang L, Longo LD. alpha(1)-Adrenergic receptor subtype function in fetal and adult cerebral arteries. Am J Physiol Heart Circ Physiol 2010; 298:H1797-806. [PMID: 20348219 PMCID: PMC2886655 DOI: 10.1152/ajpheart.00112.2010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Accepted: 03/24/2010] [Indexed: 11/22/2022]
Abstract
In the developing fetus, cerebral artery (CA) contractility demonstrates significant functional differences from that of the adult. This may be a consequence of differential activities of alpha(1)-adrenergic receptor (alpha(1)-AR) subtypes. Thus we tested the hypothesis that maturational differences in adrenergic-mediated CA contractility are, in part, a consequence of differential expression and/or activities of alpha(1)-AR subtypes. In CA from fetal ( approximately 140 days) and nonpregnant adult sheep, we used wire myography and imaging, with simultaneous measurement of tension and intracellular Ca(2+) concentration ([Ca(2+)](i)), radioimmunoassay, and Western immunoblots to examine phenylephrine (Phe)-induced contractile responses. The alpha(1A)-AR antagonists (5-MU and WB-4101) completely inhibited Phe-induced contraction in adult but not fetal CA; however, [Ca(2+)](i) increase was reduced significantly in both age groups. The alpha(1D)-AR antagonist (BMY-7378) blocked both Phe-induced contractions and Ca(2+) responses to a significantly greater extent in adult compared with fetal CA. In both age groups, inhibition of alpha(1A)-AR and alpha(1B)-AR, but not alpha(1D)-AR, significantly reduced inositol 1,4,5-trisphosphate responses to Phe. Western immunoblots demonstrated that the alpha(1)-AR subtype expression was only approximately 20% in fetal CA compared with the adult. Moreover, in fetal CA, the alpha(1D)-AR was expressed significantly greater than the other two subtypes. Also, in fetal but not adult CA, Phe induced a significant increase in activated ERK1/2; this increase in phosphorylated ERK was blocked by alpha(1B)-AR (CEC) and alpha(1D)-AR (BMY-7378) inhibitors, but not by alpha(1A)-AR inhibitors (5-MU or WB-4101). In conclusion, in the fetal CA, alpha(1B)-AR and alpha(1D)-AR subtypes play a key role in contractile response as well as in ERK activation. We speculate that in fetal CA alpha(1B)-AR and alpha(1D)-AR subtypes may be a critical factor associated with cerebrovascular growth and function.
Collapse
Affiliation(s)
- Ravi Goyal
- Center for Perinatal Biology, Department of Physiology and Pharmacology, Loma Linda Univ., School of Medicine, Loma Linda, CA 92350, USA
| | | | | | | | | |
Collapse
|
11
|
Methven L, Simpson PC, McGrath JC. Alpha1A/B-knockout mice explain the native alpha1D-adrenoceptor's role in vasoconstriction and show that its location is independent of the other alpha1-subtypes. Br J Pharmacol 2010; 158:1663-75. [PMID: 19888965 DOI: 10.1111/j.1476-5381.2009.00462.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND AND PURPOSE Theoretically, three alpha(1)-adrenoceptor subtypes can interact at the signalling level to alter vascular contraction or at the molecular level to alter each other's cellular location. The alpha(1A/B)-adrenoceptor knockout mouse (alpha(1A/B)-KO) was used to study the isolated alpha(1D)-adrenoceptor to consider these potential interactions in native tissue. EXPERIMENTAL APPROACH Pharmacological analysis of carotid and mesenteric arteries employed wire myography and fluorescent ligand binding (alpha(1)-adrenoceptor ligand BODIPY FL-prazosin, QAPB). KEY RESULTS alpha(1A/B)-KO carotid had clear alpha(1D)-adrenoceptor-induced contractions. In WT carotid alpha(1D)-adrenoceptor dominated but all three alpha(1)-subtypes participated. alpha(1A/B)-KO mesenteric had alpha(1D)-adrenoceptor responses with high sensitivity and small maximum, explaining how alpha(1D)-adrenoceptor could determine agonist sensitivity in WT. In both arteries alpha(1A/B)-KO fluorescence levels were reduced but pharmacologically more consistent with 'pure'alpha(1D)-adrenoceptors. alpha(1D)-Adrenoceptor binding in alpha(1A/B)-KO was observed on the cell surface and intracellularly and was present in a high proportion of smooth-muscle cells in both strains, regardless of artery type. CONCLUSIONS AND IMPLICATIONS 'Pure'alpha(1D)-adrenoceptor pharmacology in alpha(1A/B)-KO provides a quantitative standard. Functionally, the alpha(1D)- and alpha(1A)-adrenoceptors produce additive responses and do not significantly compensate for each other. alpha(1D)-Adrenoceptor contributes to sensitivity even in resistance arteries. In alpha(1A/B)-KO, the loss of alpha(1A)- and alpha(1B)-adrenoceptors is reflected by a general decrease in fluorescence, but similar binding distribution to WT indicates that the alpha(1D)-adrenoceptor location in native smooth-muscle cells is not influenced by other alpha(1)-adrenoceptors. Equivalent levels of receptors did not correspond to equivalent responses. In conclusion, alpha(1)-subtypes do not interact but provide independent alternative signals for vascular regulation.
Collapse
Affiliation(s)
- L Methven
- Integrative and Systems Biology, Faculty of Biomedical and Life Sciences, University of Glasgow, Glasgow, UK.
| | | | | |
Collapse
|
12
|
Cohn HI, Harris DM, Pesant S, Pfeiffer M, Zhou RH, Koch WJ, Dorn GW, Eckhart AD. Inhibition of vascular smooth muscle G protein-coupled receptor kinase 2 enhances alpha1D-adrenergic receptor constriction. Am J Physiol Heart Circ Physiol 2008; 295:H1695-704. [PMID: 18723764 PMCID: PMC2593515 DOI: 10.1152/ajpheart.00564.2008] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Accepted: 08/04/2008] [Indexed: 01/08/2023]
Abstract
G protein-coupled receptor kinase 2 (GRK2) is a serine/theorinine kinase that phosphorylates and desensitizes agonist-bound G protein-coupled receptors. GRK2 is increased in expression and activity in lymphocytes and vascular smooth muscle (VSM) in human hypertension and animal models of the disease. Inhibition of GRK2 using the carboxyl-terminal portion of the protein (GRK2ct) has been an effective tool to restore compromised beta-adrenergic receptor (AR) function in heart failure and improve outcome. A well-characterized dysfunction in hypertension is attenuation of betaAR-mediated vasodilation. Therefore, we tested the role of inhibition of GRK2 using GRK2ct or VSM-selective GRK2 gene ablation in a renal artery stenosis model of elevated blood pressure (BP) [the two-kidney, one-clip (2K1C) model]. Use of the 2K1C model resulted in a 30% increase in conscious BP, a threefold increase in plasma norepinephrine levels, and a 50% increase in VSM GRK2 mRNA levels. BP remained increased despite VSM-specific GRK2 inhibition by either GRK2 knockout (GRK2KO) or peptide inhibition (GRK2ct). Although betaAR-mediated dilation in vivo and in situ was enhanced, alpha(1)AR-mediated vasoconstriction was also increased. Further pharmacological experiments using alpha(1)AR antagonists revealed that GRK2 inhibition of expression (GRK2KO) or activity (GRK2ct) enhanced alpha(1D)AR vasoconstriction. This is the first study to suggest that VSM alpha(1D)ARs are a GRK2 substrate in vivo.
Collapse
MESH Headings
- Adrenergic beta-Agonists/pharmacology
- Adrenergic beta-Antagonists/pharmacology
- Angiotensin II/metabolism
- Animals
- Aorta/enzymology
- Blood Pressure
- Cattle
- Disease Models, Animal
- Dose-Response Relationship, Drug
- G-Protein-Coupled Receptor Kinase 2/genetics
- G-Protein-Coupled Receptor Kinase 2/metabolism
- Hypertension, Renovascular/enzymology
- Hypertension, Renovascular/etiology
- Hypertension, Renovascular/physiopathology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Norepinephrine/blood
- Receptors, Adrenergic, alpha-1/drug effects
- Receptors, Adrenergic, alpha-1/metabolism
- Renal Artery Obstruction/complications
- Renal Artery Obstruction/enzymology
- Renal Artery Obstruction/physiopathology
- Vasoconstriction/drug effects
Collapse
Affiliation(s)
- Heather Irina Cohn
- Center for Translational Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Villalobos-Molina R, Vázquez-Cuevas FG, López-Guerrero JJ, Figueroa-García MC, Gallardo-Ortiz IA, Ibarra M, Rodríguez-Sosa M, Gonzalez FJ, Elizondo G. Vascular alpha-1D-adrenoceptors are overexpressed in aorta of the aryl hydrocarbon receptor null mouse: role of increased angiotensin II. ACTA ACUST UNITED AC 2008; 28:61-7. [PMID: 18598287 DOI: 10.1111/j.1474-8673.2008.00418.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
1 The hypothesis that alpha(1D)-adrenoceptors may mediate the pro-hypertensive actions of angiotensin II (Ang II) was tested in isolated aorta (alpha(1D)-adrenoceptor bearing tissue) of the aryl hydrocarbon receptor null mouse (AhR(-/-)), which shows increased levels of Ang II, cardiac hypertrophy and hypertension. 2 The effect of captopril (an angiotensin converting enzyme inhibitor) on both blood pressure and aortic alpha(1D)-adrenoceptor expression and function in mice were determined. 3 Basal blood pressure was higher in AhR(-/-) mice, while captopril therapy decreased it to wild-type (WT) values. 4 Aortas of adult WT and AhR(-/-) mice were stimulated by phenylephrine or noradrenaline to induce contraction; the maximal effect was higher in AhR(-/-) mice, without a significant change in pEC(50). 5 PA(2) values for the selective alpha(1D)-adrenoceptor antagonist BMY 7378 (8-[2-[4-(2-methoxyphenyl)-1-piperazynil]ethyl]-8-azaspiro [4.5]decane-7,9-dione) were 9.19 and 8.94 for WT and AhR(-/-), respectively; while Schild slopes were not different from 1. 6 PCR experiments showed c. 77% increase in AhR(-/-)alpha(1D)-adrenoceptors cDNA compared with WT mice; while western blot analysis demonstrated c. 88% increase in alpha(1D)-adrenoceptor protein in AhR(-/-) mice. 7 Captopril therapy decreased alpha(1D)-adrenoceptor-induced contraction and protein in AhR(-/-) mice to WT levels. 8 These data support the hypothesis that under conditions where Ang II is elevated, vascular alpha(1D)-adrenoceptors are increased, and further suggest that both Ang II and vascular alpha(1D)-adrenoceptors could be related in the onset of hypertension.
Collapse
Affiliation(s)
- R Villalobos-Molina
- Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, México
| | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Lyssand JS, DeFino MC, Tang XB, Hertz AL, Feller DB, Wacker JL, Adams ME, Hague C. Blood pressure is regulated by an alpha1D-adrenergic receptor/dystrophin signalosome. J Biol Chem 2008; 283:18792-800. [PMID: 18468998 DOI: 10.1074/jbc.m801860200] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hypertension is a cardiovascular disease associated with increased plasma catecholamines, overactivation of the sympathetic nervous system, and increased vascular tone and total peripheral resistance. A key regulator of sympathetic nervous system function is the alpha(1D)-adrenergic receptor (AR), which belongs to the adrenergic family of G-protein-coupled receptors (GPCRs). Endogenous catecholamines norepinephrine and epinephrine activate alpha(1D)-ARs on vascular smooth muscle to stimulate vasoconstriction, which increases total peripheral resistance and mean arterial pressure. Indeed, alpha(1D)-AR KO mice display a hypotensive phenotype and are resistant to salt-induced hypertension. Unfortunately, little information exists about how this important GPCR functions because of an inability to obtain functional expression in vitro. Here, we identified the dystrophin proteins, syntrophin, dystrobrevin, and utrophin as essential GPCR-interacting proteins for alpha(1D)-ARs. We found that dystrophins complex with alpha(1D)-AR both in vitro and in vivo to ensure proper functional expression. More importantly, we demonstrate that knock-out of multiple syntrophin isoforms results in the complete loss of alpha(1D)-AR function in mouse aortic smooth muscle cells and abrogation of alpha(1D)-AR-mediated increases in blood pressure. Our findings demonstrate that syntrophin and utrophin associate with alpha(1D)-ARs to create a functional signalosome, which is essential for alpha(1D)-AR regulation of vascular tone and blood pressure.
Collapse
Affiliation(s)
- John S Lyssand
- Department of Pharmacology, University of Washington, Seattle, Washington 98195, USA
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Martínez-Salas SG, Campos-Peralta JM, Pares-Hipolito J, Gallardo-Ortíz IA, Ibarra M, Villalobos-Molina R. Alpha1A-adrenoceptors predominate in the control of blood pressure in mouse mesenteric vascular bed. ACTA ACUST UNITED AC 2007; 27:137-42. [PMID: 17584443 DOI: 10.1111/j.1474-8673.2007.00403.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
1 The pressor action of the alpha1A-adrenoceptor agonist, A61603 (N-[5-(4,5-dihydro-1H-imidazol-2-yl)-2-hydroxy-5,6,7,8-tetrahydronaphthalen-1-yl] methanesulfonamide) or the alpha1-adrenoceptor agonist phenylephrine, and their blockade by selective alpha1-adrenoceptor antagonists in the mouse isolated mesenteric vascular bed were evaluated. 2 A61603 showed a approximately 235-fold higher potency in elevating perfusion pressure in mesenteric bed compared to phenylephrine. 3 The alpha1A-adrenoceptor selective antagonist RS 100329 (5-methyl-3-[3-[4-[2-(2,2,2,-trifluoroethoxy) phenyl]-1-piperazinyl] propyl]-2,4-(1H)-pyrimidinedione), displaced with high affinity agonist concentration-response curves to the right in a concentration-dependent manner. 4 The alpha1D-adrenoceptor selective antagonist BMY 7378 (8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspiro[4.5] decane-7,9-dione), did not displace A61603 nor did it block the phenylephrine-induced pressor response. 5 The alpha1B/D-adrenoceptor alkylating antagonist chloroethylclonidine (CEC), caused a rightward shift of the phenylephrine concentration-response curve and reduced its maximum response; however, CEC only slightly modified A61603 evoked contraction. 6 The results indicate that the isolated mouse mesenteric vascular bed expresses alpha1A-adrenoceptors and suggest a very discrete role for 1B-adrenoceptors.
Collapse
Affiliation(s)
- S G Martínez-Salas
- Escuela Militar de Graduados de Sanidad, Universidad del Ejército y Fuerza Aérea, Secretaría de la Defensa Nacional, México, D.F
| | | | | | | | | | | |
Collapse
|
16
|
Kamikihara SY, Mueller A, Lima V, Akinaga J, Nojimoto FD, Castilho A, Buratini J, Pupo AS. alpha1-Adrenoceptors in proximal segments of tail arteries from control and reserpinised rats. Naunyn Schmiedebergs Arch Pharmacol 2007; 376:117-26. [PMID: 17676312 DOI: 10.1007/s00210-007-0176-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2007] [Accepted: 06/28/2007] [Indexed: 10/23/2022]
Abstract
It has been recently shown that the supersensitivity of distal segments of the rat tail artery to phenylephrine after chemical sympathectomy with reserpine results from the appearance of alpha(1D)-adrenoceptors. It is known that both alpha(1A)- and alpha(1D)-adrenoceptors are involved in the contractions of proximal portions of the rat tail artery. Therefore, this study investigated whether sympathectomy with reserpine would induce supersensitivity in proximal segments of the rat tail artery, a tissue in which alpha(1D)-adrenoceptors are already functional. Proximal segments of tail arteries from reserpinised rats were three- to sixfold more sensitive to phenylephrine and methoxamine than were arteries from control rats (n = 6-2; p < 0.05). The imidazolines N-[5-(4,5-Dihydro-1H-imidazol-2-yl)-2-hydroxy-5,6,7,8-tetrahydronaphthalen-1-yl]methanesulfonamide hydrobromide (A-61603) and oxymetazoline, which activate selectively alpha(1A)-adrenoceptors, were equipotent in tail arteries from control and reserpinised rats (n = 4-2; p < 0.05), whereas buspirone, which activates selectively alpha(1D)-adrenoceptor, was approximately 4-fold more potent in tail arteries from reserpinised rats (n = 4-6; p < 0.05). Prazosin (nonselective) and 5-methylurapidil (alpha(1A)-selective), were competitive antagonists of contractions induced by phenylephrine and were equipotent in tail arteries from control and reserpinised rats (n = 4-6). The selective alpha(1D)-adrenoceptor antagonist 8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspiro[4.5]decane-7,9-dione dihydrochloride (BMY-7378) presented similar complex antagonism in tail arteries from control and reserpinised rats, with Schild slopes much lower than 1.0 (p < 0.05, n = 4-6). Semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) revealed that mRNA encoding alpha(1A)-and alpha(1B)-adrenoceptors are similarly distributed in tail arteries from control and reserpinised rats, whereas mRNA for alpha(1D)-adrenoceptors is twice more abundant in the tail artery from reserpinised rats. In conclusion, the supersensitivity induced by reserpine is related only to alpha(1D)-adrenoceptors, even in tissues where this receptor subtype is already present and functional. Only the use of subtype-selective alpha(1)-adrenoceptor agonists detected the increased alpha(1D)-adrenoceptor component after reserpinisation, as the antagonists behaved similarly in tail arteries from control and reserpinised rats.
Collapse
MESH Headings
- Adrenergic alpha-1 Receptor Agonists
- Adrenergic alpha-1 Receptor Antagonists
- Animals
- Arteries/drug effects
- Arteries/innervation
- Arteries/metabolism
- Buspirone/pharmacology
- Gene Expression
- Imidazoles/pharmacology
- In Vitro Techniques
- Male
- Methoxamine/pharmacology
- Muscle Contraction/drug effects
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/physiology
- Oxymetazoline/pharmacology
- Phenylephrine/pharmacology
- Piperazines/pharmacology
- Prazosin/pharmacology
- RNA, Messenger/biosynthesis
- Rats
- Rats, Wistar
- Receptors, Adrenergic, alpha-1/biosynthesis
- Reserpine/pharmacology
- Reverse Transcriptase Polymerase Chain Reaction
- Sympathectomy
- Tail/blood supply
- Tetrahydronaphthalenes/pharmacology
Collapse
Affiliation(s)
- Susana Y Kamikihara
- Department of Pharmacology, Instituto de Biociências, UNESP, Botucatu, SP 18618-000, Brazil
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Tanaka Y, Funabiki M, Michikawa H, Koike K. Effects of aging on alpha1-adrenoceptor mechanisms in the isolated mouse aortic preparation. J Smooth Muscle Res 2006; 42:131-8. [PMID: 17099296 DOI: 10.1540/jsmr.42.131] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The effects of aging on alpha(1)-adrenoceptor (alpha(1)-AR)-mediated contractile response in endothelium-removed aortic preparations isolated from 5- to 40-week-old (5-, 6-, 8-, 10-, 20-, 40-weeks) mice were studied in the presence of propranolol. The potency of noradrenaline, estimated as its pD(2) value, increased with age from 5- to 10-weeks, but decreased thereafter with age from 10- to 40-weeks. However, the affinity of prazosin (pA(2) value) did not change with aging. These results suggest that age-related change in noradrenaline potency is not attributable to the change of drug affinity to alpha(1)-ARs, but is possibly due to drug affinity-unrelated factors such as change of the reserve of alpha(1)-ARs.
Collapse
Affiliation(s)
- Yoshio Tanaka
- Department of Chemical Pharmacology, Toho University School of Pharmaceutical Sciences, Funabashi, Chiba, Japan.
| | | | | | | |
Collapse
|
18
|
Lázaro-Suárez ML, Gómez-Zamudio JH, Gallardo-Ortíz IA, Tanoue A, Tsujimoto G, Farias-Rodríguez VM, Villalobos-Molina R. Chloroethylclonidine reveals that alpha (1 A)-adrenoceptors mediate contraction in aorta of alpha (1 D)-adrenoceptor knockout mice. ACTA ACUST UNITED AC 2006; 25:179-83. [PMID: 16176450 DOI: 10.1111/j.1474-8673.2005.00348.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
1 We have characterized the alpha(1)-adrenoceptor subtypes present in isolated aorta of the alpha(1D)-adrenoceptor knockout (KO) mice, by chloroethylclonidine (CEC)-induced alkylation and their protection by selective alpha(1)-adrenoceptor antagonists. 2 The alpha(1D)-adrenoceptor is involved in the contractile response to noradrenaline in wild type (WT) mouse aorta. 3 In WT mice 5-methylurapidil (5-MU, an alpha(1A)-adrenoceptor antagonist) or BMY 7378 (8-[2-[4-(2-methoxyphenyl)-1-piperazinyl] ethyl]-8-azaspiro[4.5] decane-7,9 dione, a selective alpha(1D)-adrenoceptor antagonist), protected the receptors from CEC-induced (alpha(1B/D)-adrenoceptor) alkylation, the combination of both antagonists resulted in complete protection, while AH11110A (1-[biphenyl-2-yloxy]-4-imino-4-piperidin-1-yl-butan-2-ol, an alpha(1B)-adrenoceptor antagonist) did not protect. 4 In aorta of KO mice there was a 19-fold rightward shift in noradrenaline effective concentration (EC(50)) compared with WT; while 5-MU alone or in combination with AH11110A protected alpha(1)-adrenoceptors to the same extent. 5 The data indicate that alpha(1A)-adrenoceptors mediate contraction and suggest their role in maintaining homeostasis in the alpha(1D)-adrenoceptors KO mice.
Collapse
Affiliation(s)
- M L Lázaro-Suárez
- Facultad de Ciencias Médicas y Biológicas 'Dr. Ignacio Chávez', Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mich., México
| | | | | | | | | | | | | |
Collapse
|
19
|
Hosoda C, Tanoue A, Shibano M, Tanaka Y, Hiroyama M, Koshimizu TA, Cotecchia S, Kitamura T, Tsujimoto G, Koike K. Correlation between vasoconstrictor roles and mRNA expression of alpha1-adrenoceptor subtypes in blood vessels of genetically engineered mice. Br J Pharmacol 2006; 146:456-66. [PMID: 16113694 PMCID: PMC1576278 DOI: 10.1038/sj.bjp.0706325] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We examined the contribution of each alpha(1)-adrenoceptor (AR) subtype in noradrenaline (NAd)-evoked contraction in the thoracic aortas and mesenteric arteries of mice. Compared with the concentration-response curves (CRCs) for NAd in the thoracic aortas of wild-type (WT) mice, the CRCs of mutant mice showed a significantly lower sensitivity. The pD(2) value in rank order is as follows: WT mice (8.21) > alpha(1B)-adrenoceptor knockout (alpha(1B)-KO) (7.77) > alpha(1D)-AR knockout (alpha(1D)-KO) (6.44) > alpha(1B)- and alpha(1D)-AR double knockout (alpha(1BD)-KO) (5.15). In the mesenteric artery, CRCs for NAd did not differ significantly between either WT (6.52) and alpha(1B)-KO mice (7.12) or alpha(1D)-KO (6.19) and alpha(1BD)-KO (6.29) mice. However, the CRC maximum responses to NAd in alpha(1D)- and alpha(1BD)-KO mice were significantly lower than those in WT and alpha(1B)-KO mice. Except in the thoracic aortas of alpha(1BD)-KO mice, the competitive antagonist prazosin inhibited the contraction response to NAd with high affinity. However, prazosin produced shallow Schild slopes in the vessels of mice lacking the alpha(1D)-AR gene. In the thoracic aorta, pA(2) values in WT mice for KMD-3213 and BMY7378 were 8.25 and 8.46, respectively, and in alpha(1B)-KO mice they were 8.49 and 9.13, respectively. In the mesenteric artery, pA(2) values in WT mice for KMD-3213 and BMY7378 were 8.34 and 7.47, respectively, and in alpha(1B)-KO mice they were 8.11 and 7.82, respectively. These pharmacological findings were in fairly good agreement with findings from comparison of CRCs, with the exception of the mesenteric arteries of WT and alpha(1B)-KO mice, which showed low affinities to BMY7378. We performed a quantitative analysis of the mRNA expression of each alpha(1)-AR subtype in these vessels in order to examine the correlation between mRNA expression level and the predominance of each alpha(1)-AR subtype in mediating vascular contraction. The rank order of each alpha(1)-AR subtype in terms of its vasoconstrictor role was in fairly good agreement with the level of expression of mRNA of each subtype, that is, alpha(1D)-AR > alpha(1B)-AR > alpha(1A)-AR in the thoracic aorta and alpha(1D)-AR > alpha(1A)-AR > alpha(1B)-AR in the mesenteric artery. No dramatic compensatory change of alpha(1)-AR subtype in mutant mice was observed in pharmacological or quantitative mRNA expression analysis.
Collapse
MESH Headings
- Adrenergic alpha-Antagonists/pharmacology
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/physiology
- Gene Expression Regulation/drug effects
- In Vitro Techniques
- Indoles/pharmacology
- Male
- Mesenteric Arteries/drug effects
- Mesenteric Arteries/metabolism
- Mesenteric Arteries/physiology
- Mice
- Mice, Knockout
- Norepinephrine/pharmacology
- Piperazines/pharmacology
- Prazosin/pharmacology
- RNA, Messenger/analysis
- RNA, Messenger/metabolism
- Receptors, Adrenergic, alpha-1/genetics
- Receptors, Adrenergic, alpha-1/metabolism
- Receptors, Adrenergic, alpha-1/physiology
- Vasoconstriction/drug effects
Collapse
Affiliation(s)
- Chihiro Hosoda
- Department of Pharmacology, National Research Institute for Child Health and Development, Tokyo, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Hague C, Lee SE, Chen Z, Prinster SC, Hall RA, Minneman KP. Heterodimers of alpha1B- and alpha1D-adrenergic receptors form a single functional entity. Mol Pharmacol 2005; 69:45-55. [PMID: 16195468 DOI: 10.1124/mol.105.014985] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Heterologous expression of alpha(1D)-adrenergic receptors (alpha(1D)-ARs) in most cell types results in intracellular retention and little or no functionality. We showed previously that heterodimerization with alpha(1B)-ARs promotes surface localization of alpha(1D)-ARs. Here, we report that the alpha(1B)-/alpha(1D)-AR interaction has significant effects on the pharmacology and signaling of the receptors, in addition to the effects on trafficking described previously. Upon coexpression of alpha(1B)-ARs and epitope-tagged alpha(1D)-ARs in both human embryonic kidney 293 and DDT(1)MF-2 cells, alpha(1D)-AR binding sites were not detectable with the alpha(1D)-AR selective antagonist 8-[2-(4-(2-methoxyphenyl)piperazin-1-yl)ethyl]-8-azaspiro[4,5]decane-7,9-dione (BMY 7378), despite the ability to detect alpha(1D)-AR protein using confocal microscopy, immunoprecipitation, and a luminometer cell-surface assay. However, the alpha(1B)-AR-selective mutant F18A conotoxin showed a striking biphasic inhibition in alpha(1B)/alpha(1D)-AR-expressing cells, revealing that alpha(1D)-ARs were expressed but did not bind BMY 7378 with high affinity. Studies of norepinephrine-stimulated inositol phosphate formation showed that maximal responses were greatest in alpha(1B)/alpha(1D)-AR-coexpressing cells. Stable coexpression of an uncoupled mutant alpha(1B)-AR (Delta12) with alpha(1D)-ARs resulted in increased responses to norepinephrine. However, Schild plots for inhibition of norepinephrine-stimulated inositol phosphate formation showed a single low-affinity site for BMY 7378. Thus, our findings suggest that alpha(1B)/alpha(1D)-AR heterodimers form a single functional entity with enhanced functional activity relative to either subtype alone and a novel pharmacological profile. These data may help to explain why alpha(1D)-ARs are often pharmacologically undetectable in native tissues when they are coexpressed with alpha(1B)-ARs.
Collapse
Affiliation(s)
- Chris Hague
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | | | | | | | | | | |
Collapse
|
21
|
Babamusta F, Rateri DL, Moorleghen JJ, Howatt DA, Li XA, Daugherty A. Angiotensin II infusion induces site-specific intra-laminar hemorrhage in macrophage colony-stimulating factor-deficient mice. Atherosclerosis 2005; 186:282-90. [PMID: 16153649 DOI: 10.1016/j.atherosclerosis.2005.08.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2005] [Revised: 07/29/2005] [Accepted: 08/01/2005] [Indexed: 11/30/2022]
Abstract
Angiotensin II (AngII) infusion promotes macrophage infiltration into the aortic wall resulting in several forms of vascular pathology. To determine the causal role of macrophages in these vascular diseases, we used osteopetrotic (op) male mice in which a natural mutation ablates production of M-CSF and results in severe depletion of monocytes. AngII infusion into apoE-/- mice resulted in increased atherosclerosis that was attenuated in op mice. AngII infusion in op mice unexpectedly produced grossly discernable thickening of the proximal thoracic aorta characterized by intra-mural hematoma. This pathology was also observed in apoE+/+ x op male mice, and therefore, independent of hyper-lipidemia. No perceptible structural properties of aortas from op mice could be discerned prior to AngII infusion. Regional effects in the contractile response to phenylephrine were noted in aortic rings with enhanced responsivity in the upper thoracic aortas of op mice compared to those from +/+ mice. No differences in contractile response were noted in aortic rings from the lower thorax. In conclusion, deficiency of M-CSF attenuated AngII-induced atherosclerosis but led to an unanticipated pathology of intra-laminar hemorrhage in the upper aortic regions.
Collapse
Affiliation(s)
- Fjoralba Babamusta
- Cardiovascular Research Center, Wethington Building, Room 521, University of Kentucky, Lexington, KY 40536-0200, USA
| | | | | | | | | | | |
Collapse
|
22
|
Kamikihara SY, Mueller A, Lima V, Silva ART, da Costa IB, Buratini J, Pupo AS. Differential Distribution of Functional α1-Adrenergic Receptor Subtypes along the Rat Tail Artery. J Pharmacol Exp Ther 2005; 314:753-61. [PMID: 15872040 DOI: 10.1124/jpet.105.087502] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The rat tail artery has been used for the study of vasoconstriction mediated by alpha(1A)-adrenoceptors (ARs). However, rings from proximal segments of the tail artery (within the initial 4 cm, PRTA) were at least 3-fold more sensitive to methoxamine and phenylephrine (n = 6-12; p < 0.05) than rings from distal parts (between the sixth and 10th cm, DRTA). Interestingly, the imidazolines N-[5-(4,5-dihydro-1H-imidazol-2-yl)-2-hydroxy-5,6,7,8-tetrahydronaphthalen-1-yl]methanesulfonamide hydrobromide (A-61603) and oxymetazoline, which activate selectively alpha(1A)-ARs, were equipotent in PRTA and DRTA (n = 4-12), whereas buspirone, which activates selectively alpha(1D)-AR, was approximately 70-fold more potent in PRTA than in DRTA (n = 8; p < 0.05). The selective alpha(1D)-AR antagonist 8-[2-[4-(methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspiro[4.5]decane-7,9-dione dihydrochloride (BMY-7378) was approximately 70-fold more potent against the contractions induced by phenylephrine in PRTA (pK(B) of approximately 8.45; n = 6) than in DRTA (pK(B) of approximately 6.58; n = 6), although the antagonism was complex in PRTA. 5-Methylurapidil, a selective alpha(1A)-antagonist, was equipotent in PRTA and DRTA (pK(B) of approximately 8.4), but the Schild slope in DRTA was 0.73 +/- 0.05 (n = 5). The noncompetitive alpha(1B)-antagonist conotoxin rho-TIA reduced the maximal contraction induced by phenylephrine in DRTA, but not in PRTA. These results indicate a predominant role for alpha(1A)-ARs in the contractions of both PRTA and DRTA but with significant coparticipations of alpha(1D)-ARs in PRTA and alpha(1B)-ARs in DRTA. Semiquantitative reverse transcription-polymerase chain reaction revealed that mRNA encoding alpha(1A)- and alpha(1B)-ARs are similarly distributed in PRTA and DRTA, whereas mRNA for alpha(1D)-ARs is twice more abundant in PRTA. Therefore, alpha(1)-ARs subtypes are differentially distributed along the tail artery. It is important to consider the segment from which the tissue preparation is taken to avoid misinterpretations on receptor mechanisms and drug selectivities.
Collapse
Affiliation(s)
- Susana Y Kamikihara
- Department of Pharmacology, Instituto de Biociências, UNESP, Botucatu, São Paulo, Brazil, 18618-000
| | | | | | | | | | | | | |
Collapse
|
23
|
Bexis S, Vandeputte C, McCormick PA, Docherty JR. Deletion of inducible nitric oxide synthase decreases mesenteric vascular responsiveness in portal hypertensive mice. Eur J Pharmacol 2004; 499:325-33. [PMID: 15381055 DOI: 10.1016/j.ejphar.2004.08.001] [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: 05/11/2004] [Revised: 07/29/2004] [Accepted: 08/03/2004] [Indexed: 02/09/2023]
Abstract
The effects of pre-hepatic portal hypertension were examined on the responsiveness of aorta and mesenteric artery from wild-type, inducible nitric oxide synthase knockout (iNOS-KO) and endothelial nitric oxide synthase knockout (eNOS-KO) mice. Mice were sham-operated or made portal hypertensive by creating a calibrated portal vein stenosis. Acetylcholine produced marked relaxations in phenylephrine (10 microM) contracted aorta and mesenteric artery from wild-type and iNOS-KO, both sham and portal hypertensive, but relaxations were abolished in vessels from eNOS-KO mice. There were no significant differences between sham and portal hypertensive animals within groups in the effects of acetylcholine. The potency of KCl was significantly increased in aorta and mesenteric artery from eNOS-KO mice. The maximum contraction to the alpha(1)-adrenoceptor agonist phenylephrine was significantly increased in aorta from eNOS-KO, as compared with wild-type mice. There were no significant differences between sham and portal hypertensive animals within each group in contractions of aorta to KCl or phenylephrine. However, in mesenteric artery, although portal hypertension did not change responsiveness in wild-type or eNOS-KO as compared to sham animals, the potency of phenylephrine was significantly reduced in portal hypertensive iNOS-KO mice as compared to shams. Hence, portal hypertension as compared to sham operation did not affect responses to vasoconstrictors in mouse aorta, but in mouse mesenteric artery portal hypertension affected vascular responses in iNOS-KO mice, suggesting that iNOS is involved in the mesenteric vascular response to portal vein ligation.
Collapse
Affiliation(s)
- Sotiria Bexis
- Department of Physiology, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | | | | | | |
Collapse
|
24
|
Jähnichen S, Eltze M, Pertz HH. Evidence that α1B-adrenoceptors are involved in noradrenaline-induced contractions of rat tail artery. Eur J Pharmacol 2004; 488:157-67. [PMID: 15044047 DOI: 10.1016/j.ejphar.2004.02.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2003] [Revised: 02/05/2004] [Accepted: 02/10/2004] [Indexed: 10/26/2022]
Abstract
The present study characterizes the alpha(1)-adrenoceptor subtypes mediating contractions to noradrenaline in isolated ring preparations of rat tail artery. Concentration-response (E/[A]) curves to noradrenaline were apparently monophasic (pEC(50) 6.47) but became biphasic in the presence of the selective alpha(1A)-adrenoceptor antagonist (+/-)-1,3,5-trimethyl-6-[[3-[4-((2,3-dihydro-2-hydroxymethyl)-1,4-benzodioxin-5-yl)-1-piperazinyl]propyl]amino]-2,4(1H,3H)-pyrimidinedione (B8805-033). Whereas the first phase of contraction to noradrenaline remained nearly unaffected in the presence of B8805-033 (0.03-3 microM), the second phase was concentration-dependently shifted to the right (pK(B) 8.06). In the presence of B8805-033 (3 microM), noradrenaline-induced contractions (pEC(50) 6.55) were antagonized in a competitive manner by prazosin (pK(B) 9.24), tamsulosin (pK(B) 8.55), 2-(2,6-dimethoxyphenoxyethyl)aminomethyl-1,4-benzodioxane (WB 4101; pK(B) 7.81), spiperone (pK(B) 7.69), 4-amino-2-[4-[1-(benzyloxycarbonyl)-2(S)-[[(1,1-dimethylethyl)amino]carbonyl]-piperazinyl]-6,7-dimethoxyquinazoline (L-765,314; pK(B) 7.31), 5-methylurapidil (pK(B) 6.55), 8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspiro[4.5]decane-7,9-dione (BMY 7378; pK(B) 6.43), and 8-[2-(1,4-benzodioxan-2-ylmethylamino)ethyl]-8-azaspiro[4.5]decane-7,9-dione (MDL 73005EF; pK(B) 5.71), and were also antagonized by 100 microM chloroethylclonidine. N-[2-(2-cyclopropylmethoxyphenoxy)ethyl]-5-chloro-alpha,alpha-dimethyl-1H-indole-3-ethanamine (RS-17053) behaved as a noncompetitive antagonist (apparent pA(2) 6.55). Antagonist affinities obtained under these experimental conditions correlated highly with affinities at native and cloned alpha(1B)-adrenoceptors. Pretreatment of arterial rings with B8805-033 (3 microM) followed by receptor inactivation with chloroethylclonidine (100 microM) yielded monophasic E/[A] curves to noradrenaline (pEC(50) 6.14). Noradrenaline-induced contractions were competitively antagonized by tamsulosin (pK(B) 10.32), 5-methylurapidil (pK(B) 8.66), RS-17053 (pK(B) 8.44), B8805-033 (pK(B) 7.87), BMY 7378 (pK(B) 6.54), and L-765,314 (pK(B) 6.41). Antagonist affinities obtained under these experimental conditions correlated highly with affinities at native and cloned alpha(1A)-adrenoceptors. It is concluded that the contraction to noradrenaline in rat tail artery is mediated by both alpha(1B)- and alpha(1A)-adrenoceptors, each component of contraction being separable by use of selective alpha(1A)-adrenoceptor blockade and alpha(1B)-adrenoceptor alkylation, respectively.
Collapse
Affiliation(s)
- Sven Jähnichen
- Institute of Pharmacy, Free University of Berlin, Königin-Luise-Str. 2+4, Berlin 14195, Germany
| | | | | |
Collapse
|
25
|
Vandeputte C, Aiden McCormick P, Docherty JR. Responsiveness to noradrenaline in aorta from wild-type, nitric oxide synthase-2, nitric oxide synthase-3 and alpha2A/D-adrenoceptor knockout mice. Eur J Pharmacol 2003; 466:129-36. [PMID: 12679149 DOI: 10.1016/s0014-2999(03)01535-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We have investigated the responsiveness of mouse aorta to noradrenaline (10 microM). In wild-type mice, noradrenaline produced an initial peak contraction (3.35+/-0.28 mN) and a significantly smaller plateau response (2.15+/-0.41 mN). The contractions were similar in aorta from nitric oxide synthase-2 (NOS-2) knockout mice. In vessels from NOS-3 knockout mice, noradrenaline contractions consisted of an early steeply rising phase with a later shallow rising phase to a maximum (10.21+/-0.84 mN), which was significantly greater than in wild-type and NOS-2 knockout mice, and resembled the contraction to phenylephrine (10 microM) in wild-type. In alpha(2A/D)-adrenoceptor knockout mice, the noradrenaline maximum was significantly smaller than in NOS-3 knockout but significantly larger than in wild-type. Following N(G)-nitro-L-arginine methyl ester (L-NAME, 10 microM), responses in wild-type and alpha(2A/D)-adrenoceptor knockout were as in NOS-3 knockout mice. The alpha(2D)-adrenoceptor antagonist BRL 44408 (2-((4,5-dihydro-1H-imidazole-2-yl)methyl)-2,3-di-hydro-1-methyl-1H-isoindole maleate; 1 microM) increased noradrenaline-induced contractions and the alpha(2)-adrenoceptor agonist xylazine reduced Prostaglandin F(2alpha)-induced contractions, in wild-type but not NOS-3 knockout. Contractions to noradrenaline in mouse aorta are modulated by NOS-3 and part of the effect involves activation of alpha(2A/D)-adrenoceptors.
Collapse
MESH Headings
- Adrenergic alpha-Agonists/blood
- Adrenergic alpha-Agonists/pharmacology
- Adrenergic alpha-Antagonists/pharmacology
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/physiology
- Endothelium, Vascular/drug effects
- Imidazoles/pharmacology
- In Vitro Techniques
- Indoles/pharmacology
- Isoindoles
- Male
- Mice
- Mice, Knockout
- Muscle Contraction/drug effects
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- NG-Nitroarginine Methyl Ester/pharmacology
- Nitric Oxide Synthase/deficiency
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase Type II
- Nitric Oxide Synthase Type III
- Norepinephrine/blood
- Norepinephrine/pharmacology
- Receptors, Adrenergic, alpha-2/drug effects
- Receptors, Adrenergic, alpha-2/genetics
- Receptors, Adrenergic, alpha-2/physiology
- Xylazine/pharmacology
Collapse
Affiliation(s)
- Catherine Vandeputte
- Department of Physiology, Royal College of Surgeons in Ireland, 2, Dublin, Ireland
| | | | | |
Collapse
|
26
|
Turnbull L, McCloskey DT, O'Connell TD, Simpson PC, Baker AJ. Alpha 1-adrenergic receptor responses in alpha 1AB-AR knockout mouse hearts suggest the presence of alpha 1D-AR. Am J Physiol Heart Circ Physiol 2003; 284:H1104-9. [PMID: 12595294 DOI: 10.1152/ajpheart.00441.2002] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two functional alpha(1)-adrenergic receptor (AR) subtypes (alpha(1A) and alpha(1B)) have been identified in the mouse heart. However, it is unclear whether the third known subtype, alpha(1D)-AR, is also present. To investigate this, we determined whether there were alpha(1)-AR responses in hearts from a novel mouse model lacking alpha(1A)- and alpha(1B)-ARs (double knockout) (ABKO). In Langendorff-perfused hearts, alpha(1)-ARs were stimulated with phenylephrine. For ABKO hearts, phenylephrine reduced left ventricular pressure and coronary flow (to 87 +/- 2% and 86 +/- 4% of initial, respectively, n = 11, P < 0.01). These effects were blocked by prazosin and 8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]-8-azaspirol[4,5]decane-7,9-dione] dihydrochloride, suggesting that alpha(1D)-AR-mediated responses were present. In contrast, right ventricular trabeculae from ABKO hearts did not respond to phenylephrine, suggesting that in ABKO perfused hearts, the effects of phenylephrine were not mediated by direct actions on cardiomyocytes. A novel finding was that alpha(1)-AR stimulation caused positive inotropy in the wild-type mouse heart, in contrast to negative inotropy observed in mouse cardiac muscle strips. We conclude that mouse hearts lacking alpha(1A)- and alpha(1B)-ARs retain functional alpha(1)-AR responses involving decreases of coronary flow and ventricular pressure that reflect alpha(1D)-AR-mediated vasoconstriction. Furthermore, alpha(1)-AR inotropic responses depend critically on the experimental conditions.
Collapse
Affiliation(s)
- Lynne Turnbull
- Department of Medicine and Cardiovascular Research Institute, University of California and Veterans Affairs Medical Center, San Francisco, USA
| | | | | | | | | |
Collapse
|
27
|
Shibano M, Yamamoto Y, Horinouchi T, Tanaka Y, Koike K. Pharmacological characterization of alpha1-adrenoceptor in mouse iliac artery. Eur J Pharmacol 2002; 456:77-9. [PMID: 12450572 DOI: 10.1016/s0014-2999(02)02649-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Subtypes of alpha(1)-adrenoceptor-mediated contraction to noradrenaline in the mouse iliac artery were determined (pharmaco-mechanically). Prazosin, 2-[2,6-dimethoxyphenoxyethyl]aminomethyl-1,4-benzodioxane hydrochloride (WB 4101) and 5-methylurapidil shifted the concentration-response curve for noradrenaline to the right, giving the pA(2) values of 9.30, 9.55 and 8.71, respectively. 8-[2-[4-(2-Methoxyphenyl)-1-piperazinyl]-ethyl]-8-azaspiro[4,5]decane-7,9-dione dihydrochloride (BMY 7378) shifted the concentration-response curve for noradrenaline to the right and the pA(2) value was 6.62. These results indicate that the contractile response to noradrenaline in the mouse iliac artery is predominantly mediated by the alpha(1A) -adrenoceptor subtype.
Collapse
Affiliation(s)
- Mari Shibano
- Department of Chemical Pharmacology, Toho University School of Pharmaceutical Sciences, 2-2-1, Miyama, Funabashi, Chiba, Japan
| | | | | | | | | |
Collapse
|
28
|
Hague C, Gonzalez-Cabrera PJ, Jeffries WB, Abel PW. Relationship between alpha(1)-adrenergic receptor-induced contraction and extracellular signal-regulated kinase activation in the bovine inferior alveolar artery. J Pharmacol Exp Ther 2002; 303:403-11. [PMID: 12235277 DOI: 10.1124/jpet.102.037531] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The endogenous adrenergic agonists norepinephrine (NE) and epinephrine regulate vascular tone by stimulating alpha(1)-adrenergic receptors (ARs) on smooth muscle cells to cause contraction. In addition, alpha(1)-ARs also couple to growth factor pathways, through stimulation of mitogen-activated protein kinases (MAPKs). MAPKs are a family of serine-threonine kinases that include extracellular signal-regulated kinase (ERK) and a variety of other kinases that are able to activate transcription factors when stimulated. We examined alpha(1)-AR stimulation of contraction and ERK activation in the bovine inferior alveolar artery (BIAA), using in vitro contraction studies and Western blotting. Using antagonists selective for individual adrenergic receptor types, we found that only alpha(1)-ARs were coupled to ERK activation and contraction. NE stimulated contraction (EC(50) = 11 microM) and ERK activation (EC(50) = 21 microM) with similar potency. Using alpha(1)-AR subtype-selective antagonists, we identified the alpha(1)-AR subtypes coupled to each response. Affinity values for alpha(1)-AR subtype-selective antagonists were consistent with alpha(1A)-AR-mediated contraction. In contrast, simultaneous treatment with concentrations of these antagonists selective for each alpha(1)-AR subtype (alpha(1A)-, alpha(1B)-, and alpha(1D)-AR) was required to inhibit ERK activation, suggesting that all three alpha(1)-ARs activate ERK in BIAA. Transmural electrical stimulation of BIAA segments resulted in activation of ERK, which was inhibited by the alpha(1)-AR-selective antagonist BE 2254 (2-[[beta-(4-hydroxyphenyl)ethyl]aminomethyl]-1-tetralone). These data suggest that in an intact artery, NE released from sympathetic nerves stimulates alpha(1)-ARs to cause contraction and ERK activation, and that redundancy among subtypes exists for alpha(1)-AR activation of ERK.
Collapse
Affiliation(s)
- Chris Hague
- Department of Pharmacology, Creighton University School of Medicine, Omaha, Nebraska 68178, USA.
| | | | | | | |
Collapse
|
29
|
Tanoue A, Koba M, Miyawaki S, Koshimizu TA, Hosoda C, Oshikawa S, Tsujimoto G. Role of the alpha1D-adrenergic receptor in the development of salt-induced hypertension. Hypertension 2002; 40:101-6. [PMID: 12105146 DOI: 10.1161/01.hyp.0000022062.70639.1c] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In an attempt to elucidate whether there is a specific alpha1-adrenergic receptor (alpha1-AR) subtype involved in the genesis or maintenance of hypertension, the alpha1D-AR subtype was evaluated in a model of salt-induced hypertension. The alpha1D-AR-deficient (alpha1D-/-) and control (alpha1D+/+) mice (n=8 to 14 in each group) were submitted to subtotal nephrectomy and given 1% saline as drinking water for 35 days. Blood pressure (BP) was monitored by tail-cuff readings and confirmed at the end point by direct intraarterial BP recording. The alpha1D-/- mice had a significantly (P=0.0004) attenuated increase in BP response in this protocol (baseline 94.6+/-2.8 versus end point 107.4+/-4.5 mm Hg) compared with that of their wild-type counterparts (alpha1D+/+), from a baseline 97.4+/-2.9 to an end point 139.4+/-4.5 mm Hg. Seven of 15 alpha1D+/+ mice died with edema, probably owing to renal failure, whereas 14 of 15 alpha1D-/- mice were maintained for 35 days. Body weight, renal remnant weight, and residual renal function were similar in the 2 groups, whereas the values of plasma catecholamines (epinephrine, norepinephrine, and dopamine) were higher in alpha1D+/+ than in the alpha1D-/- mice. These data suggest that alpha1D-AR plays an important role in developing a high BP in response to dietary salt-loading, and that agents having selective alpha1D-AR antagonism could have significant therapeutic potential in the treatment of hypertension.
Collapse
Affiliation(s)
- Akito Tanoue
- Department of Molecular, Cell Pharmacology, National Center for Child Health and Development Research Institute, Tokyo, Japan
| | | | | | | | | | | | | |
Collapse
|