scholarly journals Role of the Rho/Rho-kinase pathway in the development of hypertensive glomerulosclerosis: renoprotective effect of Rho-kinase inhibitor in hypertensive glomerulosclerosis and its molecular mechanism

2006 ◽  
Vol 128 (3) ◽  
pp. 153-159 ◽  
Author(s):  
Toshio Nishikimi
2003 ◽  
Vol 285 (5) ◽  
pp. R1145-R1152 ◽  
Author(s):  
Christopher J. Wingard ◽  
Shahid Husain ◽  
Jan Williams ◽  
Sharita James

Maintenance of the detumescent state of the penis is believed to involve the actions of several vasoconstrictors. However, our mechanistic understanding of any synergistic vasoconstrictor influences is extremely limited. We tested the hypothesis that a vasoconstrictor combination of endothelin (ET-1) and phenylephrine (PE) augments the constrictor responses in rat corporal cavernosal tissues by a mechanism involving the RhoA-Rho kinase pathway. Independently, ET-1 (1 nM-30 μM) and PE (100 nM-100 μM) both caused dose-dependent contractions of isolated rat cavernosal tissues. In combination, ET-1 (30 nM) augmented the contractile effect of PE and shifted the calculated EC50 for PE (90 ± 12 to 45 ± 5 μM). The active stress generated by cavernosal strips during the ET-1 + PE combined stimulation (4.9 ± 0.2 mN/mm2) was greater than the combined stress generated with ET-1 (0.4 ± 0.1 mN/mm2) or PE (3.3 ± 0.2 mN/mm2) stimulations alone. Blockade of ETA receptors (30 nM; A-127722) reversed the augmented stress generation and the Rho-kinase inhibitor Y-27632 differentially and dose-dependently relaxed the tissue. The combined constrictor effect was associated with a fourfold increase of RhoA in the membrane faction of the tissue homogenates. We conclude that the ET-1 + PE combination potentiate vasoconstriction through mutual activation of the RhoA-Rho kinase pathway. The interactions of these agonists likely play important roles in the maintenance of the flaccid state and contribute to some forms of erectile dysfunction.


2021 ◽  
Vol Volume 15 ◽  
pp. 2683-2692
Author(s):  
Mayuresh Naik ◽  
Monika Kapur ◽  
VishnuSwarup Gupta ◽  
HarinderSingh Sethi ◽  
Kartikeya Srivastava

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Michał Wiciński ◽  
Bartosz Malinowski ◽  
Paweł Rajewski ◽  
Paweł Szychta ◽  
Eryk Wódkiewicz ◽  
...  

Resveratrol (3,5,4′-trihydroxystilbene) is a chemical compound belonging to the group of polyphenols and flavonoids. The aim of the present study was to determine the influence of resveratrol application along with certain modulating factors, such as 8Br-cGMP-activator of cGMP-dependent protein kinases, HA-1077-Rho-kinase inhibitor, and Bay K8644-calcium channel agonist, on VMSCs constriction triggered by phenylephrine. Resveratrol at a dose of 10 mg/kg/24 h administered for 4 weeks reduced the reactivity of the arteries to the pressure action of catecholamines. Tests performed after four weeks of resveratrol administration showed that 8Br-cGMP at the concentrations of 0.01 mM/l and 0.1 mM/l intensifies this effect. Simultaneous resveratrol and Bay K8644 administration led to a significant decrease in contractility compared to the vessels collected from animals (Res−). This effect was dependent on the concentration of Bay K8644. Resveratrol seems to be counteractive against Bay K8644 by blocking L-type calcium channels. As the concentration of HA-1077 increased, there was a marked hyporeactivity of the vessels to the pressure effects of phenylephrine. The results indicate synergy between resveratrol and Rho-kinase inhibition.


2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Michal Behuliak ◽  
Michal Bencze ◽  
Ivana Vaněčková ◽  
Jaroslav Kuneš ◽  
Josef Zicha

Calcium sensitization mediated by RhoA/Rho kinase pathway can be evaluated either in the absence (basal calcium sensitization) or in the presence of endogenous vasoconstrictor systems (activated calcium sensitization). Our aim was to compare basal and activated calcium sensitization in three forms of experimental hypertension with increased sympathetic tone and enhanced calcium entry—spontaneously hypertensive rats (SHR), heterozygous Ren-2 transgenic rats (TGR), and salt hypertensive Dahl rats. Activated calcium sensitization was determined as blood pressure reduction induced by acute administration of Rho kinase inhibitor fasudil in conscious rats with intact sympathetic nervous system (SNS) and renin-angiotensin system (RAS). Basal calcium sensitization was studied as fasudil-dependent difference in blood pressure response to calcium channel opener BAY K8644 in rats subjected to RAS and SNS blockade. Calcium sensitization was also estimated from reduced development of isolated artery contraction by Rho kinase inhibitor Y-27632. Activated calcium sensitization was enhanced in all three hypertensive models (due to the hyperactivity of vasoconstrictor systems). In contrast, basal calcium sensitization was reduced in SHR and TGR relative to their controls, whereas it was augmented in salt-sensitive Dahl rats relative to their salt-resistant controls. Similar differences in calcium sensitization were seen in femoral arteries of SHR and Dahl rats.


2001 ◽  
Vol 85 (03) ◽  
pp. 514-520 ◽  
Author(s):  
K. Missy ◽  
M. Plantavid ◽  
C. Viala ◽  
H. Chap ◽  
P. Pacaud ◽  
...  

SummaryWe have addressed the role of Rho-kinase in the different steps of thrombin receptor agonist peptide (TRAP) -induced platelet activation. Interestingly, under physiological conditions, incubation of platelets with increasing concentrations of the specific Rho-kinase inhibitor Y-27632 resulted in a dose-dependent reversion of the aggregation induced by 10 μM TRAP, without affecting serotonin secretion. Addition of Y-27632 after three minutes of TRAP stimulation, when the maximal aggregation was reached, resulted in a rapid disaggregation of platelets. Accordingly, the early peak of myosin light chain (MLC) phosphorylation induced by TRAP was not affected by Y-27632 but its sustained phosphorylation, observed during the irreversible phase of aggregation, was dependent of Rho-kinase activity. The rapid decrease in MLC phosphorylation upon Y-27632 treatment correlated well with the specific disappearance of myosin heavy chain from the cytoskeleton and preceded platelet disaggregation. Finally, we provide evidence that secreted ADP, known to play a key role in TRAP-induced irreversible phase of aggregation, was involved in the sustained MLC phosphorylation through Rho-kinase and could be replaced by epinephrine.


2004 ◽  
Vol 287 (4) ◽  
pp. L673-L684 ◽  
Author(s):  
Jean-Marc Hyvelin ◽  
Clare O’Connor ◽  
Paul McLoughlin

Pulmonary arteries (PA) are resistant to the vasodilator effects of extracellular acidosis in systemic vessels; the mechanism underlying this difference between systemic and pulmonary circulations has not been elucidated. We hypothesized that RhoA/Rho-kinase-mediated Ca2+ sensitization pathway played a greater role in tension development in pulmonary than in systemic vascular smooth muscle and that this pathway was insensitive to acidosis. In arterial rings contracted with the α1-agonist phenylephrine (PE), the Rho-kinase inhibitor Y-27632 (≤3 μM) induced greater relaxation in precontracted PA rings than in aortic rings. In PA rings stimulated by PE, the activation of RhoA was greater than in aorta. Normocapnic acidosis (NA) induced a smaller relaxation in precontracted PA than in aorta. However, in the presence of nifedipine and thapsigargin, when PE-induced contraction was predominantly mediated by Rho-kinase, the relaxant effect of NA was reduced and similar in both vessel types. Furthermore, in the presence of Y-27632, NA induced a greater relaxation in both PA and aorta, which was similar in both vessels. Finally, in α-toxin-permeabilized smooth muscle, PE-induced contraction at constant Ca2+ activity was inhibited by Y-27632 and unaffected by acidosis. These results indicate that Ca2+ sensitization induced by the RhoA/Rho-kinase pathway played a greater role in agonist-induced vascular smooth muscle contraction in PA than in aorta and that tension mediated by this pathway was insensitive to acidosis. The predominant role of the RhoA/Rho-kinase pathway in the pulmonary vasculature may account for the resistance of this circulation to the vasodilator effect of acidosis observed in the systemic circulation.


2001 ◽  
Vol 91 (3) ◽  
pp. 1269-1273 ◽  
Author(s):  
Thomas M. Mills ◽  
Kanchan Chitaley ◽  
Christopher J. Wingard ◽  
Ronald W. Lewis ◽  
R. Clinton Webb

A recent report from this laboratory (Chitaley K, Wingard C, Webb R, Branam H, Stopper V, Lewis R, and Mills T. Nature Medicine 7: 119–122, 2001) showed that inhibition of Rho-kinase increased the erectile response (intracavernosal pressure and mean arterial pressure) by a process that does not require nitric oxide or cGMP. The present study investigated whether vasoconstrictor agents, which are active in the penis, act via the Rho-kinase pathway. Western analysis revealed RhoA and Rho-kinase protein in the penis. Treatment with the selective Rho-kinase inhibitor Y-27632 significantly increased the magnitude of the erectile response. Intracavernous administration of endothelin-1 (ET-1; 50 pmol) or methoxamine (10 μg/kg) reduced the erectile response to autonomic stimulation. If Y-27632 was given before ET-1 or methoxamine, the vasoconstrictor effect was reduced, and intracavernosal pressure and mean arterial pressure remained elevated. However, when given after methoxamine, Y-27632 had a reduced vasodilatory effect, and Y-27632 had no vasodilatory effect when given after ET-1. These findings suggest that ET-1 and methoxamine increase Rho-kinase activity in the cavernous circulation and support the hypothesis that the vasoconstriction that maintains the penis in the nonerect state is mediated, in part, by the Rho-kinase pathway.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Takashi Shiroto ◽  
Satoshi Yasuda ◽  
Ryuji Tsuburaya ◽  
Yoshitaka Ito ◽  
Hatsue Ishibashi-Ueda ◽  
...  

It has recently been reported that coronary vasoconstricting responses are enhanced at the edge of coronary segment implanted with drug-eluting stent (DES) as compared with bare-metal stent (BMS) in humans. We have previously demonstrated in animal models and humans that activation of Rho-kinase plays a key role in the molecular mechanism of coronary vasospasm. In this study, we thus examined whether Rho-kinase pathway also is involved in the DES-induced coronary hyperconstriction in vitro and in vivo. In cultured human coronary vascular smooth muscle cells, paclitaxel (10 –1000 nM, comparable tissue concentrations in humans, 24 hours) concentration-dependently up-regulated Rho-kinase expression (n=9) and increased Rho-kinase activity (10 nM, n=6). In a porcine model in vivo, DES (Taxus ™ ) and BMS (Express ™ ) were randomly implanted in the left anterior descending and circumflex coronary arteries (n=5). Four weeks after the implantation, coronary vasoconstricting responses to serotonin (5-HT, 50 and 100 μg/kg, IC) were significantly enhanced at the DES site compared with the BMS site (DES −52±4 vs. BMS −31±5%, P<0.01), and the enhanced responses were prevented by hydroxyfasudil (HF, 90 and 300 μg/kg, IC), a selective Rho-kinase inhibitor ( Figure A ). The same in vivo findings also were noted in another comparison between DES (Cypher ™ ) and BMS (Velocity ™ ) (DES −62±3% vs. BMS −41±3%, n=6, P<0.01) ( Figure B ). Histological analysis showed microthrombus formation only at the DES site. These results suggest that Rho-kinase pathway also plays an important pathogenetic role in the DES-induced coronary hyperconstricting responses.


2015 ◽  
Vol 208 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Nazila Daneshjou ◽  
Nathan Sieracki ◽  
Geerten P. van Nieuw Amerongen ◽  
Daniel E. Conway ◽  
Martin A. Schwartz ◽  
...  

The role of the RhoGTPase Rac1 in stabilizing mature endothelial adherens junctions (AJs) is not well understood. In this paper, using a photoactivatable probe to control Rac1 activity at AJs, we addressed the relationship between Rac1 and the dynamics of vascular endothelial cadherin (VE-cadherin). We demonstrated that Rac1 activation reduced the rate of VE-cadherin dissociation, leading to increased density of VE-cadherin at AJs. This response was coupled to a reduction in actomyosin-dependent tension across VE-cadherin adhesion sites. We observed that inhibiting myosin II directly or through photo-release of the caged Rho kinase inhibitor also reduced the rate of VE-cadherin dissociation. Thus, Rac1 functions by stabilizing VE-cadherin trans-dimers in mature AJs by counteracting the actomyosin tension. The results suggest a new model of VE-cadherin adhesive interaction mediated by Rac1-induced reduction of mechanical tension at AJs, resulting in the stabilization of VE-cadherin adhesions.


2005 ◽  
Vol 289 (3) ◽  
pp. H1115-H1122 ◽  
Author(s):  
Keshari Thakali ◽  
Stacie L. Demel ◽  
Gregory D. Fink ◽  
Stephanie W. Watts

Reactive oxygen species (ROS), such as superoxide and H2O2, are capable of modifying vascular tone, although the response to ROS can vary qualitatively among vascular beds, experimental procedures, and species. Endothelin-1 (ET-1) induces superoxide production, which can be dismutated to H2O2. The RhoA/Rho kinase pathway partially mediates ET-1-induced contraction and recently was implicated in superoxide-induced contraction. We hypothesized that H2O2, not superoxide, mediates venous ET-1-induced contraction. Rat thoracic aorta and vena cava contracted to exogenously added H2O2 (1 μM–1 mM) [maximum aortic contraction = 10 ± 3% of phenylephrine (10 μM) contraction; maximum venous contraction = 85 ± 13% of norepinephrine (10 μM) contraction]. (+)-( R)- trans-4-(1-aminoethyl- N-4-pyridil)cyclohexanecarboxamide dihydrochloride (Y-27632, 10 μM), a Rho kinase inhibitor, significantly reduced venous H2O2-induced contraction (15 ± 1% of control maximum) and reduced maximum ET-1-induced contraction by 59 ± 1%. However, neither the H2O2 scavenger catalase (100 and 2,000 U/ml) nor cell permeable polyethylene glycol-catalase (163 and 326 U/ml) reduced ET-1-induced contraction in the vena cava. The catalase inhibitor 3-aminotriazole (3-AT) also had no effect on maximal venous ET-1-induced contraction. Basal H2O2 levels were three times higher in the vena cava than in the aorta (vena cava, 0.74 ± 0.09 nmol H2O2/mg protein; aorta, 0.24 ± 0.05 nmol H2O2/mg protein). ET-1 (100 nM) increased H2O2 in the vena cava but not in the aorta (vena cava, 154.10 ± 17.29% of control H2O2; aorta, 83.72 ± 20.20%). Antagonism of either ETA or ETB receptors with the use of atrasentan (30 nM) or BQ-788 (100 nM), respectively, reduced ET-1 (100 nM)-induced increases in venous H2O2. In summary, ET-1 increased H2O2 in veins but not arteries, and venous ET-1-induced H2O2 production was independent of the contractile properties of ET-1.


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