1
|
Kuwabara Y, Tanaka-Ishikawa M, Abe K, Hirano M, Hirooka Y, Tsutsui H, Sunagawa K, Hirano K. Proteinase-activated receptor 1 antagonism ameliorates experimental pulmonary hypertension. Cardiovasc Res 2020; 115:1357-1368. [PMID: 30423156 DOI: 10.1093/cvr/cvy284] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 10/28/2018] [Accepted: 11/12/2018] [Indexed: 12/12/2022] Open
Abstract
AIMS Pulmonary hypertension (PH) is characterized by progressive increases in pulmonary vascular resistance (PVR). Thrombotic lesions are common pathological findings. The pulmonary artery has a unique property regarding the vasoconstrictive response to thrombin, which is mediated by proteinase-activated receptor 1 (PAR1). We aim to elucidate the role of PAR1 in the development and progression of PH. METHODS AND RESULTS A rat model of monocrotaline-induced PH and a mouse model of hypoxia (Hx)-induced PH were used to investigate the effects of atopaxar (a PAR1 antagonist) and PAR1 knockout on haemodynamic parameters, right ventricular hypertrophy (RVH), vascular remodelling and survival. In perfused lung preparations, the pressor response to PAR1 agonist was significantly augmented in monocrotaline-induced PH. Both the preventive and therapeutic administration of atopaxar significantly inhibited the increase in PVR and the development of RVH and prolonged survival. A real-time PCR revealed that the level of PAR1 mRNA in the pulmonary artery was significantly higher than that in any of the systemic arteries examined in control rats, and the level was significantly up-regulated in monocrotaline-induced PH. PAR1 gene knockout significantly attenuated the haemodynamic and histological findings in the mouse model of Hx-induced PH. CONCLUSION The specific expression of PAR1 in the pulmonary artery and its up-regulation were suggested to play a critical role in the development and progression of experimental PH in murine models. PAR1 is a potential therapeutic target for the treatment of PH.
Collapse
Affiliation(s)
- Yukimitsu Kuwabara
- Department of Molecular Cardiology, Research Institute of Angiocardiology, Graduate School of Medicine, Kyushu University, Fukuoka, Japan.,Department of Cardiovascular Medicine, Research Institute of Angiocardiology, Graduate School of Medicine, Kyushu University, Fukuoka, Japan
| | - Mariko Tanaka-Ishikawa
- Department of Cardiovascular Medicine, Research Institute of Angiocardiology, Graduate School of Medicine, Kyushu University, Fukuoka, Japan.,Department of Anesthesiology and Critical Care, Graduate School of Medicine, Kyushu University, Fukuoka, Japan
| | - Kohtaro Abe
- Department of Cardiovascular Medicine, Research Institute of Angiocardiology, Graduate School of Medicine, Kyushu University, Fukuoka, Japan
| | - Mayumi Hirano
- Department of Molecular Cardiology, Research Institute of Angiocardiology, Graduate School of Medicine, Kyushu University, Fukuoka, Japan
| | - Yoshitaka Hirooka
- Department of Advanced Cardiovascular Regulation and Therapeutics, Graduate School of Medicine, Kyushu University, Fukuoka, Japan
| | - Hiroyuki Tsutsui
- Department of Cardiovascular Medicine, Research Institute of Angiocardiology, Graduate School of Medicine, Kyushu University, Fukuoka, Japan
| | - Kenji Sunagawa
- Department of Cardiovascular Medicine, Research Institute of Angiocardiology, Graduate School of Medicine, Kyushu University, Fukuoka, Japan
| | - Katsuya Hirano
- Department of Cardiovascular Physiology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, Japan
| |
Collapse
|
2
|
Parenteral administration of factor Xa/IIa inhibitors limits experimental aortic aneurysm and atherosclerosis. Sci Rep 2017; 7:43079. [PMID: 28220880 PMCID: PMC5318894 DOI: 10.1038/srep43079] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 01/12/2017] [Indexed: 12/20/2022] Open
Abstract
Intraluminal thrombus is a consistent feature of human abdominal aortic aneurysm (AAA). Coagulation factor Xa (FXa) catalyses FII to thrombin (FIIa). We examined the effect of FXa/FIIa inhibition on experimental aortic aneurysm in apolipoprotein E-deficient (ApoE-/-) mice infused with angiotensin II (AngII). The concentration of FXa within the supra-renal aorta (SRA) correlated positively with SRA diameter. Parenteral administration of enoxaparin (FXa/IIa inhibitor) and fondaparinux (FXa inhibitor) over 14 days reduced to severity of aortic aneurysm and atherosclerosis in AngII-infused ApoE-/- mice. Enteral administration of the FIIa inhibitor dabigatran had no significant effect. Aortic protease-activated receptor (PAR)-2 expression increased in response to AngII infusion. Fondaparinux reduced SRA levels of FXa, FIIa, PAR-2, matrix metalloproteinase (MMP)2, Smad2/3 phosphorylation, and MOMA-2 positive cells in the mouse model. FXa stimulated Smad2/3 phosphorylation and MMP2 expression in aortic vascular smooth muscle cells (VSMC) in vitro. Expression of MMP2 in FXa-stimulated VSMC was downregulated in the presence of a PAR-2 but not a PAR-1 inhibitor. These findings suggest that FXa/FIIa inhibition limits aortic aneurysm and atherosclerosis severity due to down-regulation of vascular PAR-2-mediated Smad2/3 signalling and MMP2 expression. Inhibition of FXa/FIIa may be a potential therapy for limiting aortic aneurysm.
Collapse
|
3
|
Ramachandran R, Altier C, Oikonomopoulou K, Hollenberg MD. Proteinases, Their Extracellular Targets, and Inflammatory Signaling. Pharmacol Rev 2016; 68:1110-1142. [PMID: 27677721 DOI: 10.1124/pr.115.010991] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Given that over 2% of the human genome codes for proteolytic enzymes and their inhibitors, it is not surprising that proteinases serve many physiologic-pathophysiological roles. In this context, we provide an overview of proteolytic mechanisms regulating inflammation, with a focus on cell signaling stimulated by the generation of inflammatory peptides; activation of the proteinase-activated receptor (PAR) family of G protein-coupled receptors (GPCR), with a mechanism in common with adhesion-triggered GPCRs (ADGRs); and by proteolytic ion channel regulation. These mechanisms are considered in the much wider context that proteolytic mechanisms serve, including the processing of growth factors and their receptors, the regulation of matrix-integrin signaling, and the generation and release of membrane-tethered receptor ligands. These signaling mechanisms are relevant for inflammatory, neurodegenerative, and cardiovascular diseases as well as for cancer. We propose that the inflammation-triggering proteinases and their proteolytically generated substrates represent attractive therapeutic targets and we discuss appropriate targeting strategies.
Collapse
Affiliation(s)
- Rithwik Ramachandran
- Inflammation Research Network-Snyder Institute for Chronic Disease, Department of Physiology & Pharmacology (R.R., C.A., M.D.H.) and Department of Medicine (M.D.H.),University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada; Department of Pathology and Laboratory Medicine, Toronto Western Hospital, Toronto, Ontario, Canada (K.O.); and Department of Physiology and Pharmacology, Western University, London, Ontario, Canada (R.R.)
| | - Christophe Altier
- Inflammation Research Network-Snyder Institute for Chronic Disease, Department of Physiology & Pharmacology (R.R., C.A., M.D.H.) and Department of Medicine (M.D.H.),University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada; Department of Pathology and Laboratory Medicine, Toronto Western Hospital, Toronto, Ontario, Canada (K.O.); and Department of Physiology and Pharmacology, Western University, London, Ontario, Canada (R.R.)
| | - Katerina Oikonomopoulou
- Inflammation Research Network-Snyder Institute for Chronic Disease, Department of Physiology & Pharmacology (R.R., C.A., M.D.H.) and Department of Medicine (M.D.H.),University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada; Department of Pathology and Laboratory Medicine, Toronto Western Hospital, Toronto, Ontario, Canada (K.O.); and Department of Physiology and Pharmacology, Western University, London, Ontario, Canada (R.R.)
| | - Morley D Hollenberg
- Inflammation Research Network-Snyder Institute for Chronic Disease, Department of Physiology & Pharmacology (R.R., C.A., M.D.H.) and Department of Medicine (M.D.H.),University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada; Department of Pathology and Laboratory Medicine, Toronto Western Hospital, Toronto, Ontario, Canada (K.O.); and Department of Physiology and Pharmacology, Western University, London, Ontario, Canada (R.R.)
| |
Collapse
|
4
|
Gieseler F, Ungefroren H, Settmacher U, Hollenberg MD, Kaufmann R. Proteinase-activated receptors (PARs) - focus on receptor-receptor-interactions and their physiological and pathophysiological impact. Cell Commun Signal 2013; 11:86. [PMID: 24215724 PMCID: PMC3842752 DOI: 10.1186/1478-811x-11-86] [Citation(s) in RCA: 138] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 10/25/2013] [Indexed: 02/07/2023] Open
Abstract
Proteinase-activated receptors (PARs) are a subfamily of G protein-coupled receptors (GPCRs) with four members, PAR1, PAR2, PAR3 and PAR4, playing critical functions in hemostasis, thrombosis, embryonic development, wound healing, inflammation and cancer progression. PARs are characterized by a unique activation mechanism involving receptor cleavage by different proteinases at specific sites within the extracellular amino-terminus and the exposure of amino-terminal “tethered ligand“ domains that bind to and activate the cleaved receptors. After activation, the PAR family members are able to stimulate complex intracellular signalling networks via classical G protein-mediated pathways and beta-arrestin signalling. In addition, different receptor crosstalk mechanisms critically contribute to a high diversity of PAR signal transduction and receptor-trafficking processes that result in multiple physiological effects. In this review, we summarize current information about PAR-initiated physical and functional receptor interactions and their physiological and pathological roles. We focus especially on PAR homo- and heterodimerization, transactivation of receptor tyrosine kinases (RTKs) and receptor serine/threonine kinases (RSTKs), communication with other GPCRs, toll-like receptors and NOD-like receptors, ion channel receptors, and on PAR association with cargo receptors. In addition, we discuss the suitability of these receptor interaction mechanisms as targets for modulating PAR signalling in disease.
Collapse
Affiliation(s)
| | | | | | | | - Roland Kaufmann
- Department of General, Visceral and Vascular Surgery, Experimental Transplantation Surgery, Jena University Hospital, Drackendorfer Str, 1, D-07747, Jena, Germany.
| |
Collapse
|
5
|
Jobi K, Rauch BH, Dangwal S, Freidel K, Doller A, Eberhardt W, Fischer JW, Schrör K, Rosenkranz AC. Redox regulation of human protease-activated receptor-2 by activated factor X. Free Radic Biol Med 2011; 51:1758-64. [PMID: 21871560 DOI: 10.1016/j.freeradbiomed.2011.08.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Revised: 07/12/2011] [Accepted: 08/05/2011] [Indexed: 11/16/2022]
Abstract
Activated factor X (FXa) exerts coagulation-independent actions such as proliferation of vascular smooth muscle cells (SMCs) through the protease-activated receptors PAR-1 and PAR-2. Both receptors are upregulated upon vascular injury but the underlying mechanisms have not been defined. We examined if FXa regulates PAR-1 and PAR-2 in human vascular SMCs. FXa increased PAR-2 mRNA, protein, and cell-surface expression and augmented PAR-2-mediated mitogenesis. PAR-1 was not influenced. The regulatory action of FXa on PAR-2 was concentration-dependent and mimicked by a PAR-2-selective activating peptide. PAR-2 regulation was not influenced by the thrombin inhibitor argatroban or PAR-1 siRNA. FXa increased dichlorofluorescein diacetate fluorescence and 8-isoprostane formation and induced expression of the NADPH oxidase subunit NOX-1. NOX-1 siRNA prevented FXa-stimulated PAR-2 regulation, as did ebselen and cell-permeative and impermeative forms of catalase. Exogenous H(2)O(2) increased PAR-2 expression and mitogenic activity. FXa promoted nuclear translocation and PAR-2/DNA binding of nuclear factor κB (NF-κB); NF-κB inhibition prevented PAR-2 regulation by FXa. FXa also promoted PAR-2 mRNA stabilization through increased human antigen R (HuR)/PAR-2 mRNA binding and cytoplasmic shuttling. HuR siRNA abolished FXa-stimulated PAR-2 expression. Thus FXa induces functional expression of PAR-2 but not of PAR-1 in human SMCs, independent of thrombin formation, via a mechanism involving NOX-1-containing NADPH oxidase, H(2)O(2), NF-κB, and HuR.
Collapse
Affiliation(s)
- Klaus Jobi
- Institut für Pharmakologie und Klinische Pharmakologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Chieng-Yane P, Bocquet A, Létienne R, Bourbon T, Sablayrolles S, Perez M, Hatem SN, Lompré AM, Le Grand B, David-Dufilho M. Protease-Activated Receptor-1 Antagonist F 16618 Reduces Arterial Restenosis by Down-Regulation of Tumor Necrosis Factor α and Matrix Metalloproteinase 7 Expression, Migration, and Proliferation of Vascular Smooth Muscle Cells. J Pharmacol Exp Ther 2010; 336:643-51. [DOI: 10.1124/jpet.110.175182] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
7
|
Maki J, Hirano M, Hoka S, Kanaide H, Hirano K. Involvement of reactive oxygen species in thrombin-induced pulmonary vasoconstriction. Am J Respir Crit Care Med 2010; 182:1435-44. [PMID: 20639439 DOI: 10.1164/rccm.201002-0255oc] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
RATIONALE Pulmonary vascular thrombosis and thrombotic arteriopathy are common pathological findings in pulmonary arterial hypertension. Thrombin may thus play an important role in the pathogenesis and pathophysiology of pulmonary arterial hypertension. OBJECTIVES The present study aimed to elucidate the contractile effect of thrombin in the pulmonary artery and clarify its underlying mechanisms. METHODS The changes in cytosolic Ca²(+) concentrations ([Ca²(+)](i)), 20-kD myosin light chain (MLC20) phosphorylation, and contraction were monitored in the isolated porcine pulmonary artery. The production of reactive oxygen species (ROS) was evaluated by fluorescence imaging. MEASUREMENTS AND MAIN RESULTS In the presence of extracellular Ca²(+), thrombin induced a sustained contraction accompanied by an increase in [Ca²(+)](i) and the phosphorylation of MLC20. In the absence of extracellular Ca²(+), thrombin induced a contraction without either [Ca²(+)](i) elevation or MLC20 phosphorylation. This Ca²(+)- and MLC20 phosphorylation-independent contraction was mimicked by hydrogen peroxide and inhibited by N-acetyl cysteine. Fluorescence imaging revealed thrombin to induce the production of ROS. A Rho-kinase inhibitor, Y27632, inhibited not only the thrombin-induced Ca²(+)- and MLC20 phosphorylation-dependent contraction, but also the Ca²(+)- and MLC20 phosphorylation-independent contraction and the ROS production. These effects of thrombin were mimicked by a proteinase-activated receptor 1 (PAR₁)-activating peptide. CONCLUSIONS This study elucidated the Ca²(+)- and MLC20 phosphorylation-independent ROS-mediated noncanonical mechanism as well as Ca²(+)- and MLC20 phosphorylation-dependent canonical mechanism that are involved in the thrombin-induced PAR₁-mediated pulmonary vasoconstriction. Rho-kinase was suggested to play multiple roles in the development of thrombin-induced pulmonary vasoconstriction.
Collapse
Affiliation(s)
- Jun Maki
- Research Institute of Angiocardiology, Kyushu University, Higashi-ku, Fukuoka, Japan
| | | | | | | | | |
Collapse
|
8
|
Maki J, Hirano M, Hoka S, Kanaide H, Hirano K. Thrombin activation of proteinase-activated receptor 1 potentiates the myofilament Ca2+ sensitivity and induces vasoconstriction in porcine pulmonary arteries. Br J Pharmacol 2010; 159:919-27. [PMID: 20128804 DOI: 10.1111/j.1476-5381.2009.00591.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Thrombus formation is commonly associated with pulmonary arterial hypertension (PAH). Thrombin may thus play an important role in the pathogenesis and pathophysiology of PAH. Hence, we investigated the contractile effects of thrombin and its mechanism in pulmonary artery. EXPERIMENTAL APPROACH The cytosolic Ca(2+) concentrations ([Ca(2+)](i)), 20 kDa myosin light chain (MLC20) phosphorylation and tension development were evaluated using the isolated porcine pulmonary artery. KEY RESULTS Thrombin induced a sustained contraction in endothelium-denuded strips obtained from different sites of a pulmonary artery, ranging from the main pulmonary artery to the intrapulmonary artery. In the presence of endothelium, thrombin induced a transient relaxation. The contractile effect of thrombin was abolished by either a protease inhibitor or a proteinase-activated receptor 1 (PAR(1)) antagonist, while it was mimicked by PAR(1)-activating peptide (PAR(1)AP), but not PAR(4)AP. The thrombin-induced contraction was associated with a small elevation of [Ca(2+)](i) and an increase in MLC20 phosphorylation. Thrombin and PAR(1)AP induced a greater increase in tension for a given [Ca(2+)](i) elevation than that obtained with high K(+)-depolarization. They also induced a contraction at a fixed Ca(2+) concentration in alpha-toxin-permeabilized preparations. CONCLUSIONS AND IMPLICATIONS The present study revealed a unique property of the pulmonary artery. In contrast to normal arteries of the systemic circulation, thrombin induces a sustained contraction in the normal pulmonary artery, by activating PAR(1) and thereby increasing the sensitivity of the myofilament to Ca(2+). This responsiveness of the pulmonary artery to thrombin may therefore contribute to the pathogenesis and pathophysiology of PAH.
Collapse
Affiliation(s)
- Jun Maki
- Division of Molecular Cardiology, Research Institute of Angiocardiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | | | | | | | | |
Collapse
|
9
|
Matsumoto T, Ishida K, Taguchi K, Kobayashi T, Kamata K. Mechanisms underlying enhanced vasorelaxant response to protease-activated receptor 2-activating peptide in type 2 diabetic Goto-Kakizaki rat mesenteric artery. Peptides 2009; 30:1729-34. [PMID: 19540892 DOI: 10.1016/j.peptides.2009.06.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Revised: 06/10/2009] [Accepted: 06/11/2009] [Indexed: 01/06/2023]
Abstract
Protease-activated receptor 2 (PAR2) is a G-protein-coupled receptor that is proteolytically activated by certain endogenous proteases, such as trypsin, tryptase, and factor Xa. PAR2 can also be activated by synthetic peptides if their sequence mimics the tethered ligand exposed after receptor cleavage. Although it is known that PAR2 modulates vascular reactivity, it is unclear whether at the chronic stage of type 2 diabetes there are alterations in PAR2-mediated vascular responses. We investigated this issue by exposing mesenteric artery rings to PAR2-activating peptide (PAR2-AP; SLIGRL-NH(2)), the arteries used being obtained from later-stage (32-40-week-old) type 2 diabetic Goto-Kakizaki (GK) rats. The PAR2-AP-induced relaxation was enhanced in GK rats (vs. age-matched Wistar rats), whereas the ACh-induced relaxation was weaker in GK than in Wistar rats. In both groups, the PAR2-AP-induced relaxation was largely blocked by endothelial denudation or by N(G)-nitro-L-arginine [nitric oxide (NO) synthase inhibitor] treatment, but it was unaffected by indomethacin (cyclooxygenase inhibitor) treatment. Both the NO production induced by PAR2-AP and the PAR2 protein expression were significantly increased in mesenteric arteries from GK rats (vs. Wistar rats). These data are the first to indicate that the PAR2-AP-induced endothelium-dependent relaxation is enhanced in mesenteric arteries isolated from type 2 diabetic GK rats at the chronic stage, and they further suggest that the enhancement may be due to an increased expression of PAR2 receptors in this artery.
Collapse
Affiliation(s)
- Takayuki Matsumoto
- Department of Physiology and Morphology, Institute of Medicinal Chemistry, Hoshi University, Shinagawa-ku, Tokyo, Japan
| | | | | | | | | |
Collapse
|
10
|
Bocquet A, Létienne R, Sablayrolles S, De Vries L, Perez M, Le Grand B. Effects of a new PAR1 antagonist, F 16618, on smooth muscle cell contraction. Eur J Pharmacol 2009; 611:60-3. [DOI: 10.1016/j.ejphar.2009.03.056] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 03/10/2009] [Accepted: 03/23/2009] [Indexed: 11/25/2022]
|
11
|
McGuire JJ, Van Vliet BN, Halfyard SJ. Blood pressures, heart rate and locomotor activity during salt loading and angiotensin II infusion in protease-activated receptor 2 (PAR2) knockout mice. BMC PHYSIOLOGY 2008; 8:20. [PMID: 18939990 PMCID: PMC2573878 DOI: 10.1186/1472-6793-8-20] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Accepted: 10/21/2008] [Indexed: 01/06/2023]
Abstract
Background In this study we used radiotelemetry to measure hemodynamic variables and locomotor activity in conscious unrestrained male Protease-Activated Receptor 2 (PAR-2) knockout mice in order to provide a detailed assessment of their blood pressure phenotype. In addition we tested for an influence of PAR-2 on salt-sensitivity (8% versus 0.5% NaCl diet, 2.5 weeks) and angiotensin II-induced hypertension (1 μg Ile5-angiotensin II/kg/min versus 0.25 μl/h saline, 2 weeks). Results Systolic arterial pressures of PAR-2 -/- (129 ± 1 mmHg, n = 21, P < 0.05) were statistically higher than those of C57BL/6J (124 ± 1 mmHg, n = 33) throughout the 24 h period under baseline conditions. Pulse pressures in PAR-2 -/- were also significantly elevated (33 ± 1 mmHg versus 30 ± 1 mmHg, P < 0.05), whereas diastolic arterial pressures were not. Heart rates in PAR-2 -/- were not significantly different than controls, with the exception that heart rate of PAR-2 -/- was 23 beats per min higher than controls (P < 0.001) during periods of nocturnal activity. The diurnal pattern and intensity of locomotor activity were not found to differ between strains. A high salt diet led to increased blood pressures, decreased heart rates, increased time spent active and decreased intensity levels of locomotor activity. Salt-induced changes in systolic and pulse pressures in PAR-2 -/- were less than in C57B/6J. Angiotensin II treatment increased pressures, decreased heart rates, decreased time spent active and decreased intensity levels of activity of PAR-2 -/-, all to the same extent as C57BL/6J. A trend of lower blood pressures during the middle period of angiotensin II treatment period was observed in individual PAR-2 -/-. Conclusion The data indicated gene knockout of PAR-2 was associated with a modest change in blood pressure phenotype. PAR-2 -/- mice exhibited moderate elevation of systolic arterial and pulse pressures, yet no increased diastolic arterial pressure, no increased blood pressure responses to high salt diet and a subtle difference in the time course of the blood pressure responses to angiotensin II infusion.
Collapse
Affiliation(s)
- John J McGuire
- Cardiovascular Research Group, Division of BioMedical Sciences, Faculty of Medicine, Memorial University, St. John's, Newfoundland, Canada.
| | | | | |
Collapse
|
12
|
Hartmannsgruber V, Heyken WT, Kacik M, Kaistha A, Grgic I, Harteneck C, Liedtke W, Hoyer J, Köhler R. Arterial response to shear stress critically depends on endothelial TRPV4 expression. PLoS One 2007; 2:e827. [PMID: 17786199 PMCID: PMC1959246 DOI: 10.1371/journal.pone.0000827] [Citation(s) in RCA: 212] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Accepted: 08/09/2007] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND In blood vessels, the endothelium is a crucial signal transduction interface in control of vascular tone and blood pressure to ensure energy and oxygen supply according to the organs' needs. In response to vasoactive factors and to shear stress elicited by blood flow, the endothelium secretes vasodilating or vasocontracting autacoids, which adjust the contractile state of the smooth muscle. In endothelial sensing of shear stress, the osmo- and mechanosensitive Ca(2+)-permeable TRPV4 channel has been proposed to be candidate mechanosensor. Using TRPV4(-/-) mice, we now investigated whether the absence of endothelial TRPV4 alters shear-stress-induced arterial vasodilation. METHODOLOGY/PRINCIPAL FINDINGS In TRPV4(-/-) mice, loss of the TRPV4 protein was confirmed by Western blot, immunohistochemistry and by in situ-patch-clamp techniques in carotid artery endothelial cells (CAEC). Endothelium-dependent vasodilation was determined by pressure myography in carotid arteries (CA) from TRPV4(-/-) mice and wild-type littermates (WT). In WT CAEC, TRPV4 currents could be elicited by TRPV4 activators 4alpha-phorbol-12,13-didecanoate (4alphaPDD), arachidonic acid (AA), and by hypotonic cell swelling (HTS). In striking contrast, in TRPV4(-/-) mice, 4alphaPDD did not produce currents and currents elicited by AA and HTS were significantly reduced. 4alphaPDD caused a robust and endothelium-dependent vasodilation in WT mice, again conspicuously absent in TRPV4(-/-) mice. Shear stress-induced vasodilation could readily be evoked in WT, but was completely eliminated in TRPV4(-/-) mice. In addition, flow/reperfusion-induced vasodilation was significantly reduced in TRPV4(-/-) vs. WT mice. Vasodilation in response to acetylcholine, vasoconstriction in response to phenylephrine, and passive mechanical compliance did not differ between genotypes, greatly underscoring the specificity of the above trpv4-dependent phenotype for physiologically relevant shear stress. CONCLUSIONS/SIGNIFICANCE Genetically encoded loss-of-function of trpv4 results in a loss of shear stress-induced vasodilation, a response pattern critically dependent on endothelial TRPV4 expression. Thus, Ca(2+)-influx through endothelial TRPV4 channels is a molecular mechanism contributing significantly to endothelial mechanotransduction.
Collapse
Affiliation(s)
| | - Willm-Thomas Heyken
- Department of Internal Medicine-Nephrology, Philipps-University, Marburg, Germany
| | - Michael Kacik
- Department of Internal Medicine-Nephrology, Philipps-University, Marburg, Germany
| | - Anuradha Kaistha
- Department of Internal Medicine-Nephrology, Philipps-University, Marburg, Germany
| | - Ivica Grgic
- Department of Internal Medicine-Nephrology, Philipps-University, Marburg, Germany
| | - Christian Harteneck
- Institut für Pharmakologie, Charité Campus Benjamin Franklin, Berlin, Germany
| | - Wolfgang Liedtke
- Center for Translational Neuroscience, Duke University, Durham, North Carolina, United States of America
| | - Joachim Hoyer
- Department of Internal Medicine-Nephrology, Philipps-University, Marburg, Germany
| | - Ralf Köhler
- Department of Internal Medicine-Nephrology, Philipps-University, Marburg, Germany
- * To whom correspondence should be addressed. E-mail:
| |
Collapse
|
13
|
Maeda Y, Hirano K, Kai Y, Hirano M, Suzuki SO, Sasaki T, Kanaide H. Up-regulation of proteinase-activated receptor 1 and increased contractile responses to thrombin after subarachnoid haemorrhage. Br J Pharmacol 2007; 152:1131-9. [PMID: 17767169 PMCID: PMC2095114 DOI: 10.1038/sj.bjp.0707435] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND AND PURPOSE The mechanism for the development of post-haemorrhagic cerebral vasospasm after subarachnoid haemorrhage (SAH) still remains unknown. EXPERIMENTAL APPROACH We investigated the role of thrombin and its receptor PAR1 in the development of hyper-contractility of the basilar artery in a rabbit double haemorrhage model, which received two injections of autologous blood into the cisterna magna. KEY RESULTS In the basilar artery isolated from the control rabbits, thrombin, only at 10 units ml(-1), induced a transient endothelium-dependent relaxation and a slight smooth muscle contraction. In SAH, the contractile response to thrombin was markedly enhanced, while the endothelium-dependent relaxant effect of thrombin remained unchanged. The enhancement of the contractile responses was also observed in the absence of endothelium and thrombin induced an enhanced contraction at concentrations higher than 0.3 units ml(-1). The contractile response to PAR1-activating peptide was also enhanced after SAH. However, the contractile responses to high K+ and endothelin-1, and the myofilament Ca2+-sensitivity remained unchanged after SAH. An immunoblot analysis suggested the up-regulation of PAR1 in the smooth muscle of the basilar artery. The heparinization of blood before injection prevented the enhancement of the contractile responses to thrombin and PAR1-activating peptide. CONCLUSIONS AND IMPLICATIONS The present study demonstrated, for the first time, that the contractile response of the basilar artery to thrombin was markedly enhanced after SAH. Mechanistically, our findings suggested that the activation of thrombin following hemorrhage up-regulated the expression of PAR1, thereby inducing the hyper-responsiveness to thrombin.
Collapse
MESH Headings
- Animals
- Basilar Artery/drug effects
- Basilar Artery/metabolism
- Basilar Artery/physiopathology
- Calcium/pharmacology
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Heparin/pharmacology
- Male
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiopathology
- Organ Culture Techniques
- Potassium/pharmacology
- Rabbits
- Receptor, PAR-1/agonists
- Receptor, PAR-1/biosynthesis
- Receptor, PAR-1/metabolism
- Subarachnoid Hemorrhage/physiopathology
- Thrombin/metabolism
- Thrombin/pharmacology
- Up-Regulation/drug effects
- Vasoconstriction/drug effects
- Vasospasm, Intracranial/physiopathology
Collapse
Affiliation(s)
- Y Maeda
- Division of Molecular Cardiology, Research Institute of Angiocardiology, Graduate School of Medical Sciences, Kyushu University Higashi-ku, Fukuoka, Japan
- Department of Neurosurgery, Graduate School of Medical Sciences, Kyushu University Higashi-ku, Fukuoka, Japan
| | - K Hirano
- Division of Molecular Cardiology, Research Institute of Angiocardiology, Graduate School of Medical Sciences, Kyushu University Higashi-ku, Fukuoka, Japan
| | - Y Kai
- Division of Molecular Cardiology, Research Institute of Angiocardiology, Graduate School of Medical Sciences, Kyushu University Higashi-ku, Fukuoka, Japan
| | - M Hirano
- Division of Molecular Cardiology, Research Institute of Angiocardiology, Graduate School of Medical Sciences, Kyushu University Higashi-ku, Fukuoka, Japan
| | - S O Suzuki
- Department of Neuropathology, Graduate School of Medical Sciences, Kyushu University Higashi-ku, Fukuoka, Japan
| | - T Sasaki
- Department of Neurosurgery, Graduate School of Medical Sciences, Kyushu University Higashi-ku, Fukuoka, Japan
| | - H Kanaide
- Division of Molecular Cardiology, Research Institute of Angiocardiology, Graduate School of Medical Sciences, Kyushu University Higashi-ku, Fukuoka, Japan
- Kyushu University COE Program on Lifestyle-related Disease, Kyushu University Higashi-ku, Fukuoka, Japan
- Author for correspondence:
| |
Collapse
|