scholarly journals Upregulation of Na+/Ca2+ exchanger and TRPC6 contributes to abnormal Ca2+ homeostasis in arterial smooth muscle cells from Milan hypertensive rats

2010 ◽  
Vol 299 (3) ◽  
pp. H624-H633 ◽  
Author(s):  
Alessandra Zulian ◽  
Sergey G. Baryshnikov ◽  
Cristina I. Linde ◽  
John M. Hamlyn ◽  
Patrizia Ferrari ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Smooth Muscle ◽  
Plasma Membrane ◽  
Smooth Muscle Cells ◽  
Mesenteric Artery ◽  
Transient Receptor Potential ◽  
Receptor Potential ◽  
Muscle Cells ◽  
Mesenteric Arteries ◽  
Membrane Microdomains

The Milan hypertensive strain (MHS) of rats is a model for hypertension in humans. Inherited defects in renal function have been well studied in MHS rats, but the mechanisms that underlie the elevated vascular resistance are unclear. Altered Ca2+ signaling plays a key role in the vascular dysfunction associated with arterial hypertension. Here we compared Ca2+ signaling in mesenteric artery smooth muscle cells from MHS rats and its normotensive counterpart (MNS). Systolic blood pressure was higher in MHS than in MNS rats (144 ± 2 vs. 113 ± 1 mmHg, P < 0.05). Resting cytosolic free Ca2+ concentration (measured with fura-2) and ATP-induced Ca2+ transients were augmented in freshly dissociated arterial myocytes from MHS rats. Ba2+ entry activated by the diacylglycerol analog 1-oleoyl-2-acetyl- sn-glycerol (a measure of receptor-operated channel activity) was much greater in MHS than MNS arterial myocytes. This correlated with a threefold upregulation of transient receptor potential canonical 6 (TRPC6) protein. TRPC3, the other component of receptor-operated channels, was marginally, but not significantly, upregulated. The expression of TRPC1/5, components of store-operated channels, was not altered in MHS mesenteric artery smooth muscle. Immunoblots also revealed that the Na+/Ca2+ exchanger-1 (NCX1) was greatly upregulated in MHS mesenteric artery (by ∼13-fold), whereas the expression of plasma membrane Ca2+-ATPase was not altered. Ca2+ entry via the reverse mode of NCX1 evoked by the removal of extracellular Na+ induced a rapid increase in cytosolic free Ca2+ concentration that was significantly larger in MHS arterial myocytes. The expression of α1/α2 Na+ pumps in MHS mesenteric arteries was not changed. Immunocytochemical observations showed that NCX1 and TRPC6 are clustered in plasma membrane microdomains adjacent to the underlying sarcoplasmic reticulum. In summary, MHS arteries exhibit upregulated TRPC6 and NCX1 and augmented Ca2+ signaling. We suggest that the increased Ca2+ signaling contributes to the enhanced vasoconstriction and elevated blood pressure in MHS rats.

scholarly journals Orai1, a critical component of store-operated Ca2+ entry, is functionally associated with Na+/Ca2+ exchanger and plasma membrane Ca2+ pump in proliferating human arterial myocytes

2009 ◽  
Vol 297 (5) ◽  
pp. C1103-C1112 ◽  
Author(s):  
Sergey G. Baryshnikov ◽  
Maria V. Pulina ◽  
Alessandra Zulian ◽  
Cristina I. Linde ◽  
Vera A. Golovina
Keyword(s):  
Cell Proliferation ◽  
Smooth Muscle ◽  
Plasma Membrane ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Transient Receptor Potential ◽  
Muscle Cells ◽  
Membrane Microdomains ◽  
Trpc Channels ◽  
Critical Component

Ca2+ entry through store-operated channels (SOCs) in the plasma membrane plays an important role in regulation of vascular smooth muscle contraction, tone, and cell proliferation. The C-type transient receptor potential (TRPC) channels have been proposed as major candidates for SOCs in vascular smooth muscle. Recently, two families of transmembrane proteins, Orai [also known as Ca2+ release-activated Ca2+ channel modulator (CRACM)] and stromal interacting molecule 1 (STIM1), were shown to be essential for the activation of SOCs mainly in nonexcitable cells. Here, using small interfering RNA, we show that Orai1 plays an essential role in activating store-operated Ca2+ entry (SOCE) in primary cultured proliferating human aortic smooth muscle cells (hASMCs), whereas Orai2 and Orai3 do not contribute to SOCE. Knockdown of Orai1 protein expression significantly attenuated SOCE. Moreover, inhibition of Orai1 downregulated expression of Na+/Ca2+ exchanger type 1 (NCX1) and plasma membrane Ca2+ pump isoform 1 (PMCA1). The rate of cytosolic free Ca2+ concentration decay after Ca2+ transients in Ca2+-free medium was also greatly decreased under these conditions. This reduction of Ca2+ extrusion, presumably via NCX1 and PMCA1, may be a compensation for the reduced SOCE. Immunocytochemical observations indicate that Orai1 and NCX1 are clustered in plasma membrane microdomains. Cell proliferation was attenuated in hASMCs with disrupted Orai1 expression and reduced SOCE. Thus Orai1 appears to be a critical component of SOCE in proliferating vascular smooth muscle cells, and may therefore be a key player during vascular growth and remodeling.

The Action of Shenmai Injection on the Inflammation and Proliferation of Smooth Muscle Cells of the Airway in Asthmatic Rats

2021 ◽  
Vol 11 (3) ◽  
pp. 386-391
Author(s):  
He Zhu ◽  
Yali Guo ◽  
Xiaoli Wang ◽  
Min Zhu ◽  
Jiahui Lei ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Transient Receptor Potential ◽  
Receptor Potential ◽  
Muscle Cells ◽  
Interleukin 4 ◽  
Nuclear Antigen ◽  
Control Group ◽  
Airway Smooth Muscle Cells ◽  
Shenmai Injection

To observe the effect of transient receptor potential ankyrin 1 (TRPA1) channel on the proliferation and inflammation of airway smooth muscle cells (SMC) in asthmatic rats, the rats were randomly allocated into three treatment groups: control, asthma, and Shenmai injection (SMI), with 15 rats in each group. Asthmatic rat models were induced by ovalbumin (OVA) inhalation. Rats in the control and asthma groups were intraperitoneally injected 2 mL NS daily, whereas rats in the SMI treatment group were intraperitoneally injected with 2 mL SMI daily. RT-qPCR and western blotting were used to test for TRPA1 and proliferating cell nuclear antigen (PCNA) mRNA and protein expression. ELISA was used to test the expression of interleukin-4 (IL-4), interleukin-5 (IL-5), and interleukin-13 (IL-13) in the serum. Compared with the control group, there were significantly higher levels of TRPA1 and PCNA mRNA and protein, as well as of IL-4, IL-5, and IL-13 in asthmatic rats (P< 0.05). After SMI treatment, there was significantly lower expression of TRPA1, PCNA, IL-4, IL-5, and IL-13 compared to the levels in asthmatic rats (P < 0.05). TRPA1, IL-4, IL-5, and IL-13 were highly expressed in the tracheal SMC of asthmatic rats. Inhibiting TRPA1, IL-4, IL-5, and IL-13 using SMI may be one of the mechanisms that can intervene chronic airway inflammation and asthma proliferation.

Pulmonary artery smooth muscle cells from normal subjects and IPAH patients show divergent cAMP-mediated effects on TRPC expression and capacitative Ca2+ entry

2007 ◽  
Vol 292 (5) ◽  
pp. L1202-L1210 ◽  
Author(s):  
Shen Zhang ◽  
Hemal H. Patel ◽  
Fiona Murray ◽  
Carmelle V. Remillard ◽  
Christian Schach ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Pulmonary Artery ◽  
Smooth Muscle Cells ◽  
Transient Receptor Potential ◽  
Phosphodiesterase Inhibitor ◽  
Receptor Potential ◽  
Muscle Cells ◽  
Normal Subjects ◽  
Pulmonary Artery Smooth Muscle ◽  
The Impact

Pulmonary vascular remodeling due to overgrowth of pulmonary artery smooth muscle cells (PASMC) is a major cause for the elevated vascular resistance in patients with idiopathic pulmonary arterial hypertension (IPAH). Increased cytosolic Ca2+ concentration, resulting from enhanced capacitative Ca2+ entry (CCE) and upregulated transient receptor potential (TRP) channel expression, is involved in stimulating PASMC proliferation. The current study was designed to determine the impact of cAMP, a second messenger that we hypothesized would blunt aspects of PASMC activity, as a possible contributor to IPAH pathophysiology. Short-term (30 min) pretreatment with forskolin (FSK; 10 μM), a direct activator of adenylyl cyclase, in combination with the cyclic nucleotide phosphodiesterase inhibitor isobutylmethylxanthine (IBMX; 200 μM), attenuated CCE in PASMC from normal subjects, patients without pulmonary hypertension (NPH), and patients with IPAH. The FSK-mediated CCE inhibition was independent of protein kinase A (PKA), because the PKA inhibitor H89 negligibly affected the decrease in CCE produced by cAMP. By contrast, longer (4 h) treatment with FSK (with IBMX) attenuated CCE in normal and NPH PASMC but enhanced CCE in IPAH PASMC. This enhancement of CCE was abolished by PKA inhibition and associated with an upregulation of TRPC3. In addition, cAMP increased TRPC1 mRNA expression in IPAH (but not in normal or NPH) PASMC, an effect blunted by H89. Furthermore, iloprost, a prostacyclin analog that increases cAMP, downregulated TRPC3 expression in IPAH PASMC and FSK-mediated cAMP increase inhibited IPAH PASMC proliferation. Although a rapid rise in cellular cAMP decreases CCE by a PKA-independent mechanism, sustained cAMP increase inhibits CCE in normal and NPH PASMC but increases CCE via a PKA-dependent pathway in IPAH PASMC. The divergent effect of cAMP on CCE parallels effects on TRPC expression. The results suggest that the combined use of a PKA inhibitor and cAMP-elevating drugs may provide a novel approach for treatment of IPAH.

Expression of voltage-dependent K+ channel genes in mesenteric artery smooth muscle cells

1999 ◽  
Vol 277 (5) ◽  
pp. G1055-G1063 ◽  
Author(s):  
Chuanli Xu ◽  
Yanjie Lu ◽  
Guanghua Tang ◽  
Rui Wang
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Mesenteric Artery ◽  
Muscle Cells ◽  
Mesenteric Arteries ◽  
Delayed Rectifier ◽  
Kv Channel ◽  
Channel Proteins ◽  
Voltage Dependent ◽  
Encoding Genes

Molecular basis of native voltage-dependent K+(Kv) channels in smooth muscle cells (SMCs) from rat mesenteric arteries was investigated. The whole cell patch-clamp study revealed that a 4-aminopyridine-sensitive delayed rectifier K+ current ( I K) was the predominant K+ conductance in these cells. A systematic screening of the expression of 18 Kv channel genes using RT-PCR technique showed that six I K-encoding genes (Kv1.2, Kv1.3, Kv1.5, Kv2.1, Kv2.2, and Kv3.2) were expressed in mesenteric artery. Although no transient outward Kv currents ( I A) were recorded in the studied SMCs, transcripts of multiple I A-encoding genes, including Kv1.4, Kv3.3, Kv3.4, Kv4.1, Kv4.2, and Kv4.3 as well as I A-facilitating Kv β-subunits (Kvβ1, Kvβ2, and Kvβ3), were detected in mesenteric arteries. Western blot analysis demonstrated that four I K-related Kv channel proteins (Kv1.2, Kv1.3, Kv1.5, and Kv2.1) were detected in mesenteric artery tissues. The presence of Kv1.2, Kv1.3, Kv1.5, and Kv2.1 channel proteins in isolated SMCs was further confirmed by immunocytochemistry study. Our results suggest that the native I K in rat mesenteric artery SMCs might be generated by heteromultimerization of Kv genes.

Hydrogen peroxide is a critical regulator of the hypoxia-induced alterations of store-operated Ca2+ entry into rat pulmonary arterial smooth muscle cells

2017 ◽  
Vol 312 (4) ◽  
pp. L477-L487 ◽  
Author(s):  
Tao-Xiang Chen ◽  
Xiao-Ya Xu ◽  
Zhao Zhao ◽  
Fang-Yu Zhao ◽  
Yi-Mei Gao ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Transient Receptor Potential ◽  
Receptor Potential ◽  
Muscle Cells ◽  
Arterial Smooth Muscle ◽  
Pulmonary Arterial ◽  
Arterial Smooth Muscle Cells ◽  
Pulmonary Arterial Smooth Muscle

To investigate the association between store-operated Ca2+ entry (SOCE) and reactive oxygen species (ROS) during hypoxia, this study determined the changes of transient receptor potential canonical 1 (TRPC1) and Orai1, two candidate proteins for store-operated Ca2+ (SOC) channels and their gate regulator, stromal interaction molecule 1 (STIM1), in a hypoxic environment and their relationship with ROS in pulmonary arterial smooth muscle cells (PASMCs). Exposure to hypoxia caused a transient Ca2+ spike and subsequent Ca2+ plateau of SOCE to be intensified in PASMCs when TRPC1, STIM1, and Orai1 were upregulated. SOCE in cells transfected with specific short hairpin RNA (shRNA) constructs was almost completely eliminated by the knockdown of TRPC1, STIM1, or Orai1 alone and was no longer affected by hypoxia exposure. Hypoxia-induced SOCE enhancement was further strengthened by PEG-SOD but was attenuated by PEG-catalase, with correlated changes to intracellular hydrogen peroxide (H2O2) levels and protein levels of TRPC1, STIM1, and Orai1. Exogenous H2O2 could mimic alterations of the interactions of STIM1 with TRPC1 and Orai1 in hypoxic cells. These findings suggest that TRPC1, STIM1, and Orai1 are essential for the initiation of SOCE in PASMCs. Hypoxia-induced ROS promoted the expression and interaction of the SOC channel molecules and their gate regulator via their converted product, H2O2.

TRPC1 and Orai1 interact with STIM1 and mediate capacitative Ca2+ entry caused by acute hypoxia in mouse pulmonary arterial smooth muscle cells

2012 ◽  
Vol 303 (11) ◽  
pp. C1156-C1172 ◽  
Author(s):  
Lih Chyuan Ng ◽  
Kathryn G. O'Neill ◽  
Dominique French ◽  
Judith A. Airey ◽  
Cherie A. Singer ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Transient Receptor Potential ◽  
Acute Hypoxia ◽  
Receptor Potential ◽  
Muscle Cells ◽  
Quench Rate ◽  
Transfected Cells ◽  
Fura 2 ◽  
In Cells

Previous studies in pulmonary artery smooth muscle cells (PASMCs) showed that acute hypoxia activates capacitative Ca2+ entry (CCE) but the molecular candidate(s) mediating CCE caused by acute hypoxia remain unclear. The present study aimed to determine if transient receptor potential canonical 1 (TRPC1) and Orai1 interact with stromal interacting molecule 1 (STIM1) and mediate CCE caused by acute hypoxia in mouse PASMCs. In primary cultured PASMCs loaded with fura-2, acute hypoxia caused a transient followed by a sustained rise in intracellular Ca2+ concentration ([Ca2+]i). The transient but not sustained rise in [Ca2+]i was partially inhibited by nifedipine. Acute hypoxia also increased the rate of Mn2+ quench of fura-2 fluorescence that was inhibited by SKF 96365, Ni2+, La3+, and Gd3+, exhibiting pharmacological properties characteristic of CCE. The nifedipine-insensitive rise in [Ca2+]i and the increase in Mn2+ quench rate were both inhibited in cells treated with TRPC1 antibody or TRPC1 small interfering (si)RNA, in STIM1 siRNA-transfected cells and in Orai1 siRNA-transfected cells. Moreover, overexpression of STIM1 resulted in a marked increase in [Ca2+]i and Mn2+ quench rate caused by acute hypoxia, and they were reduced in cells treated with TRPC1 antibody and in cells transfected with Orai1 siRNA. Furthermore, TRPC1 and Orai1 coimmunoprecipitated with STIM1 and the precipitation levels of TRPC1 and Orai1 were increased in cells exposed to acute hypoxia. Immunostaining showed colocalizations of TRPC1-STIM1 and Orai1-STIM1, and the colocalizations of these proteins were more apparent in acute hypoxia. These data provide direct evidence that TRPC1 and Orai1 channels mediate CCE through activation of STIM1 in acute hypoxic mouse PASMCs.

Hydrogen sulfide-induced relaxation of resistance mesenteric artery beds of rats

2004 ◽  
Vol 287 (5) ◽  
pp. H2316-H2323 ◽  
Author(s):  
Youqin Cheng ◽  
Joseph Fomusi Ndisang ◽  
Guanghua Tang ◽  
Kun Cao ◽  
Rui Wang
Keyword(s):  
Smooth Muscle ◽  
Hydrogen Sulfide ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vascular Smooth Muscle Cells ◽  
Mesenteric Artery ◽  
Muscle Cells ◽  
Mesenteric Arteries ◽  
Vascular Effects ◽  
Rat Mesenteric Artery

Hydrogen sulfide (H2S) has been shown recently to function as an important gasotransmitter. The present study investigated the vascular effects of H2S, both exogenously applied and endogenously generated, on resistance mesenteric arteries of rats and the underlying mechanisms. Both H2S and NaHS evoked concentration-dependent relaxation of in vitro perfused rat mesenteric artery beds (MAB). The sensitivity of MAB to H2S (EC50, 25.2 ± 3.6 μM) was about fivefold higher than that of rat aortic tissues. Removal of endothelium or coapplication of charybdotoxin and apamin to endothelium-intact MAB significantly reduced the vasorelaxation effects of H2S. The H2S-induced relaxation of MAB was partially mediated by ATP-sensitive K+ (KATP) channel activity in vascular smooth muscle cells. Pinacidil (EC50, 1.7 ± 0.1 μM, n = 6) mimicked, but glibenclamide (10 μM, n = 6) suppressed, the vasorelaxant effect of H2S. KATP channel currents in isolated mesenteric artery smooth muscle cells were significantly augmented by H2S. l-Cysteine, a substrate of cystathionine-γ-lyase (CSE), at 1 mM increased endogenous H2S production by sixfold in rat mesenteric artery tissues and decreased contractility of MAB. dl-Propargylglycine (a blocker of CSE) at 10 μM abolished l-cysteine-dependent increase in H2S production and relaxation of MAB. Our results demonstrated a tissue-specific relaxant response of resistance arteries to H2S. The stimulation of KATP channels in vascular smooth muscle cells and charybdotoxin/apamin-sensitive K+ channels in vascular endothelium by H2S represents important cellular mechanisms for H2S effect on MAB. Our study also demonstrated that endogenous CSE can generate sufficient H2S from exogenous l-cysteine to cause vasodilation. Future studies are merited to investigate direct contribution of endogenous H2S to regulation of vascular tone.

Sign in / Sign up

Export Citation Format

Share Document