scholarly journals High blood pressure associates with the remodelling of inward rectifier K+channels in mice mesenteric vascular smooth muscle cells

2012 ◽  
Vol 590 (23) ◽  
pp. 6075-6091 ◽  
Author(s):  
Sendoa Tajada ◽  
Pilar Cidad ◽  
Alejandro Moreno-Domínguez ◽  
M. Teresa Pérez-García ◽  
José R. López-López
Keyword(s):  
Blood Pressure ◽  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
High Blood Pressure ◽  
Vascular Smooth Muscle Cells ◽  
Muscle Cells ◽  
Inward Rectifier ◽  
K Channels

scholarly journals RGS5 Attenuates Baseline Activity of ERK1/2 and Promotes Growth Arrest of Vascular Smooth Muscle Cells

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1748
Author(s):  
Eda Demirel ◽  
Caroline Arnold ◽  
Jaspal Garg ◽  
Marius Andreas Jäger ◽  
Carsten Sticht ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Map Kinase ◽  
Vascular Smooth Muscle Cells ◽  
Muscle Cells ◽  
Genetic Ablation ◽  
Variable Expression ◽  
Arterial Blood

The regulator of G-protein signaling 5 (RGS5) acts as an inhibitor of Gαq/11 and Gαi/o activity in vascular smooth muscle cells (VSMCs), which regulate arterial tone and blood pressure. While RGS5 has been described as a crucial determinant regulating the VSMC responses during various vascular remodeling processes, its regulatory features in resting VSMCs and its impact on their phenotype are still under debate and were subject of this study. While Rgs5 shows a variable expression in mouse arteries, neither global nor SMC-specific genetic ablation of Rgs5 affected the baseline blood pressure yet elevated the phosphorylation level of the MAP kinase ERK1/2. Comparable results were obtained with 3D cultured resting VSMCs. In contrast, overexpression of RGS5 in 2D-cultured proliferating VSMCs promoted their resting state as evidenced by microarray-based expression profiling and attenuated the activity of Akt- and MAP kinase-related signaling cascades. Moreover, RGS5 overexpression attenuated ERK1/2 phosphorylation, VSMC proliferation, and migration, which was mimicked by selectively inhibiting Gαi/o but not Gαq/11 activity. Collectively, the heterogeneous expression of Rgs5 suggests arterial blood vessel type-specific functions in mouse VSMCs. This comprises inhibition of acute agonist-induced Gαq/11/calcium release as well as the support of a resting VSMC phenotype with low ERK1/2 activity by suppressing the activity of Gαi/o.

Diminished Lipid Raft SNAP23 Increases Blood Pressure by Inhibiting the Membrane Fluidity of Vascular Smooth-Muscle Cells

2015 ◽  
Vol 52 (5) ◽  
pp. 321-333 ◽  
Author(s):  
Mi So Yoon ◽  
Kyung-Jong Won ◽  
Do-Yoon Kim ◽  
Dae Il Hwang ◽  
Seok Won Yoon ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Membrane Fluidity ◽  
Vascular Smooth Muscle Cells ◽  
Lipid Raft ◽  
Muscle Cells

scholarly journals EDHF: an update

2009 ◽  
Vol 117 (4) ◽  
pp. 139-155 ◽  
Author(s):  
Michel Félétou ◽  
Paul M. Vanhoutte
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vascular Smooth Muscle Cells ◽  
Electrical Coupling ◽  
Muscle Cells ◽  
Therapeutic Interventions ◽  
K Channels ◽  
Acid Metabolites

The endothelium controls vascular tone not only by releasing NO and prostacyclin, but also by other pathways causing hyperpolarization of the underlying smooth muscle cells. This characteristic was at the origin of the term ‘endothelium-derived hyperpolarizing factor’ (EDHF). However, this acronym includes different mechanisms. Arachidonic acid metabolites derived from the cyclo-oxygenases, lipoxygenases and cytochrome P450 pathways, H2O2, CO, H2S and various peptides can be released by endothelial cells. These factors activate different families of K+ channels and hyperpolarization of the vascular smooth muscle cells contribute to the mechanisms leading to their relaxation. Additionally, another pathway associated with the hyperpolarization of both endothelial and vascular smooth muscle cells contributes also to endothelium-dependent relaxations (EDHF-mediated responses). These responses involve an increase in the intracellular Ca2+ concentration of the endothelial cells, followed by the opening of SKCa and IKCa channels (small and intermediate conductance Ca2+-activated K+ channels respectively). These channels have a distinct subcellular distribution: SKCa are widely distributed over the plasma membrane, whereas IKCa are preferentially expressed in the endothelial projections toward the smooth muscle cells. Following SKCa activation, smooth muscle hyperpolarization is preferentially evoked by electrical coupling through myoendothelial gap junctions, whereas, following IKCa activation, K+ efflux can activate smooth muscle Kir2.1 and/or Na+/K+-ATPase. EDHF-mediated responses are altered by aging and various pathologies. Therapeutic interventions can restore these responses, suggesting that the improvement in the EDHF pathway contributes to their beneficial effect. A better characterization of EDHF-mediated responses should allow the determination of whether or not new drugable targets can be identified for the treatment of cardiovascular diseases.

Abstract 524: Extracellular Guanosine Regulates Extracellular Adenosine Levels

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Edwin K Jackson ◽  
Delbert G Gillespie
Keyword(s):  
Blood Pressure ◽  
Endothelial Cells ◽  
Smooth Muscle ◽  
Coronary Artery ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vascular Smooth Muscle Cells ◽  
Muscle Cells ◽  
Extracellular Adenosine ◽  
Arterial Blood

Extracellular adenosine modulates cardiovascular and renal function. While measuring extracellular purines in biological samples, we observed a correlation between levels of adenosine and guanosine. This observation led us to test the hypothesis that extracellular guanosine regulates extracellular adenosine levels in the cardiovascular and renal systems. Rat preglomerular vascular smooth muscle cells in culture were incubated with adenosine and/or guanosine. In the absence of added adenosine, exogenous guanosine (30 μmol/L) had little effect on extracellular adenosine levels, indicating that extracellular guanosine does not trigger the release or production of adenosine. Without added guanosine and 1 hour after adding 3 μmol/L of exogenous adenosine, extracellular adenosine levels were only 0.125 ± 0.020 μmol/L, indicating rapid disposition of extracellular adenosine by a monolayer of cells. In contrast, extracellular adenosine levels 1 hour after adding 3 μmol/L of adenosine plus guanosine (30 μmol/L) were 1.173 ± 0.061 μmol/L (9-fold higher; p<0.0001), indicating slow disposition of extracellular adenosine in the presence of extracellular guanosine. Extracellular guanosine impeded the disposition of extracellular adenosine not only in preglomerular vascular smooth muscle cells, but also in rat preglomerular vascular endothelial cells, mesangial cells, cardiac fibroblasts and kidney epithelial cells, as well as in human aortic vascular smooth muscle cells, coronary artery vascular smooth muscle cells and coronary artery endothelial cells. In rats, infusions of guanosine per se had little effect on cardiovascular/renal variables, yet markedly enhanced the effects of co-infusions of adenosine. For example, in control rats, adenosine (0.3 μmol/kg/min) only modestly decreased mean arterial blood pressure (from 114 ± 4 to 100 ± 4 mm Hg). In contrast, in guanosine-treated rats (10 μmol/kg/min), adenosine profoundly decreased blood pressure (from 109 ± 4 to 79 ± 3 mm Hg; p<0.0001 vs non-guanosine treated group). Conclusion: Extracellular guanosine powerfully regulates extracellular adenosine levels by altering adenosine disposition and this occurs in many, perhaps most, cell types in the cardiovascular system and kidneys.

scholarly journals Activation of Inward Rectifier K+ Channel 2.1 by PDGF-BB in Rat Vascular Smooth Muscle Cells through Protein Kinase A

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Chengchun Tang ◽  
Dong Wang ◽  
Erfei Luo ◽  
Gaoliang Yan ◽  
Bo Liu ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Protein Kinase ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Protein Kinase A ◽  
Vascular Smooth Muscle Cells ◽  
Muscle Cells ◽  
Inward Rectifier ◽  
Kinase A ◽  
Stimulation Of

Platelet-derived growth factor-BB (PDGF-BB) can induce the proliferation, migration, and phenotypic modulation of vascular smooth muscle cells (VSMCs). We used patch clamp methods to study the effects of PDGF-BB on inward rectifier K+ channel 2.1 (Kir2.1) channels in rat thoracic aorta VSMCs (RASMCs). PDGF-BB (25 ng/mL) increased Kir2.x currents (−11.81±2.47 pA/pF, P<0.05 vs. CON, n=10). Ba2+(50 μM) decreased Kir2.x currents (−2.13±0.23 pA/pF, P<0.05 vs. CON, n=10), which were promoted by PDGF-BB (−6.98±1.03 pA/pF). PDGF-BB specifically activates Kir2.1 but not Kir2.2 and Kir2.3 channels in HEK-293 cells. The PDGF-BB-induced stimulation of Kir2.1 currents was blocked by the PDGF-BB receptor β (PDGF-BBRβ) inhibitor AG1295 and was not affected by the PDGF-BBRα inhibitor AG1296. The PDGF-BB-induced stimulation of Kir2.1 currents was blocked by the protein kinase A inhibitor Rp-8-CPT-cAMPs; however, the antagonist of protein kinase B (GSK690693) had marginal effects on current activity. The PDGF-BB-induced stimulation of Kir2.1 currents was enhanced by forskolin, an adenylyl cyclase (AC) activator, and was blocked by the AC inhibitor SQ22536. We conclude that PDGF-BB increases Kir2.1 currents via PDGF-BBRβ through activation of cAMP-PKA signaling in RASMCs.

Sign in / Sign up

Export Citation Format

Share Document