Role of miR-124 and miR-141 in the regulation of vascular reactivity and the relationship to RhoA and Rac1 after hemorrhage and hypoxia

2016 ◽  
Vol 310 (2) ◽  
pp. H206-H216 ◽  
Author(s):  
Liangming Liu ◽  
Jiatao Zang ◽  
Xiangyun Chen ◽  
Guangming Yang ◽  
Yu Zhu ◽  
...  
Keyword(s):  
Vascular Function ◽  
Vascular Reactivity ◽  
Treatment Protocol ◽  
Mesenteric Arteries ◽  
Related Factor ◽  
Mutual Regulation ◽  
Vascular Hyporeactivity ◽  
Regulatory Effects ◽  
Underlying Mechanisms ◽  
The Relationship

Recent studies show that hypoxia can alter expression levels of microRNAs (miRNAs). Whether hypoxia or hemorrhage-induced vascular hyporeactivity is related to miRNAs and the underlying mechanisms of this process is not clear. Using hypoxia-treated superior mesenteric arteries (SMAs) and vascular smooth muscle cells (VSMCs) of rats that underwent hemorrhage, we observed the regulatory effects of miR-124/miR-141 on vascular reactivity, the relationship of these miRNAs to RhoA and Rac1, and the mutual regulation of miR-124 and miR-141. The contractile responses of SMAs and VSMCs showed an increase in early stages and a decrease in late stages of hypoxia and hemorrhage. Forty-five miRNAs appeared to have been significantly changed in SMAs after hypoxia, and miR-124 and miR-141 underwent the most change. Overexpressed miR-124 or miR-141 and their antisenses appeared to alter both vascular reactivity and expression of the proteins RhoA and Rac1 after hypoxia. miR-124 inhibited Rac1 by acting at the Rac1 mRNA 3′-untranslated region (UTR), but it led to an increase in RhoA by inhibiting miR-141. miR-141 inhibited RhoA by acting at the RhoA mRNA 3′-UTR, but it led to an increase in Rac1 by inhibiting miR-124. Further study found that miR-124 inhibited miR-141 via transcription factor early growth response gene-1 (Egr-1), whereas miR-141 inhibited miR-124 via transcription of nuclear factor erythroid 2-related factor 2 (Nrf-2). These results suggest that miR-124 and miR-141 participate in the regulation of vascular reactivity after hypoxia and hemorrhage by regulating expression of the RhoA and Rac1 proteins, and in doing so, miR-124 and miR-141 are mutually regulated. These findings provide potential targets for restoring vascular function as part of the treatment protocol for hemorrhagic shock and some other critical illness.

scholarly journals Food Restriction Augmented Alpha1 Adrenergic Mediated Contraction in Mesenteric Arteries

2021 ◽  
Author(s):  
Rany Vorn ◽  
Hae Young Yoo
Keyword(s):  
Nitric Oxide ◽  
Arterial Pressure ◽  
Vascular Function ◽  
Food Restriction ◽  
Vascular Reactivity ◽  
Hypovolemic Shock ◽  
Mesenteric Arteries ◽  
Sprague Dawley ◽  
Underlying Mechanisms ◽  
Endothelial Nitric Oxide

Food restriction (FR) enhances the sensitivity to cardiopulmonary reflexes and alpha1 adrenoreceptors in the female, despite hypotension. The effect of male FR on cardiopulmonary and systemic vascular function is not well understood. This study examines the effects of FR on cardiopulmonary, isolated mesenteric arterial function and potential underlying mechanisms. We hypothesized that FR decreased eNOS activity in mesenteric arteries. Male Sprague Dawley (SD) rats were randomly divided into three groups: (1) control (n=30), (2) 20 percent of food reduction (FR20, n=30), and (3) 40 percent of food reduction (FR40, n=30) for five weeks. Non-invasive blood pressure was measured twice a week. Pulmonary arterial pressure (PAP) was measured using isolated/perfused lungs in rats. The isolated vascular reactivity was assessed in double-wire myograph. After five weeks, food restricted rats exhibited a lower mean arterial pressure and heart rate, however, only FR40 groups exhibited statistically significant differences. The basal tone of PAP and various vasoconstrictors did not show significant differences in pulmonary circulation between each group. We observed that food restriction were enhanced the sensitivity (EC50) in response to α1-adrenoreceptors (phenylephrine, PhE)-induced vasoconstriction, but not to serotonin, U46619, and high K+ in the mesenteric arteries. FR reduced endothelium-dependent relaxation via decreased function of endothelial nitric oxide synthase (eNOS)-nitric oxide (NO) pathway in the mesenteric arteries. PhE-mediated vasoconstriction in mesenteric arteries was eliminated in the presence of eNOS inhibitor (L-NAME). In addition, incubation with NOX2/4 inhibitors (apocynin, GKT137831, VAS2870) and reactive oxygen species (ROS) scavenger inhibitor (Tiron) were eliminated the differences of PhE-mediated vasoconstriction but not to cyclooxygenase inhibitor (indomethacin) in the mesenteric artery. Augmentation of alpha1 adrenergic mediated contraction via inhibition of eNOS-NO pathway by increased activation of ROS through NOX2/4 in response to FR. Reduced eNOS-NO signaling might be a pathophysiological counterbalance to prevent hypovolemic shock in response to FR.

Abstract P217: Nox Compartmentalization, Protein Oxidation and ER Stress in Vascular Smooth Muscle Cells in Hypertension

Hypertension ◽  
2017 ◽  
Vol 70 (suppl_1) ◽  
Author(s):  
Livia L Camargo ◽  
Augusto C Montezano ◽  
Adam Harvey ◽  
Sofia Tsiropoulou ◽  
Katie Hood ◽  
...  
Keyword(s):  
Er Stress ◽  
Protein Oxidation ◽  
Vascular Function ◽  
Vascular Reactivity ◽  
Stress Proteins ◽  
Vascular Dysfunction ◽  
Mesenteric Arteries ◽  
Resistance Arteries ◽  
Post Translational Modification ◽  
Wistar Kyoto

In hypertension, activation of NADPH oxidases (Noxs) is associated with oxidative stress and vascular dysfunction. The exact role of each isoform in hypertension-associated vascular injury is still unclear. We investigated the compartmentalization of Noxs in VSMC from resistance arteries of Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR). Expression of Nox1 and Nox4 was increased in SHR cells (96.6±28.7% and 48.2±21.2% vs WKY, p<0.05), as well as basal ROS levels measured by chemiluminescence (110.2±26.4% vs WKY, p<0.05) and amplex red (105.2±33.2% vs WKY, p<0.05). Phosphorylation of unfolded protein response activators, PERK and IRE1α, and expression of ER chaperone BiP were elevated in SHR cells (p<0.05 vs WKY), indicating activation of ER stress response. Immunoblotting after organelle fractionation demonstrated that Noxs are expressed in an organelle-specific manner, with Nox1, 2 and 4 present in plasma membrane, ER and nucleus, but not in mitochondria. In SHR cells, NoxA1ds (Nox1 inhibitor, 10μM) and GKT136901 (Nox1/4 inhibitor, 10μM) decreased AngII-induced ROS levels (p<0.001 vs Ctl). Additionally, mito-tempol (mitochondrial-targeted antioxidant, 50nM) and 4-PBA (ER stress inhibitor, 1mM) decreased basal ROS levels in SHR cells (p<0.05 vs Ctl). Furthermore, oxidation of the antioxidant enzymes Peroxiredoxins (Prx) was increased in SHRSP compared to WKY (2.51±0.14 vs 0.56±0.07, p<0.001). One-dimensional isoelectric focusing revealed that cytosolic Prx2 and mitochondrial Prx3 were more oxidized in SHRSP than WKY cells. Using a biotin-tagged dimedone-based probe (DCP-Bio) we identified oxidation of ER stress proteins BiP and IRE1. To investigate the effect of protein oxidation in vascular function, vascular reactivity was evaluated in isolated mesenteric arteries. Inhibition of general oxidation (DTT 1mM; Emax: 111.7±33.1) and peroxiredoxin (Conoidin A 10nM; Emax: 116.0±7.3) reduces vascular contraction in response to noradrenalin in WKY rats (Emax: 166.6±30.2; p<0.05). These findings suggest an important role for Nox1/4 in redox-dependent organelle dysfunction and post-translational modification of proteins, processes that may play an important role in vascular dysfunction in hypertension.

Abstract 138: Altered Vascular Reactivity in Mice Overexpressing Adipocyte Mineralocorticoid Receptors - Role of Rho Kinase.

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Aurelie Nguyen Dinh Cat ◽  
Tayze T Antunes ◽  
Glaucia E Callera ◽  
Augusto C Montezano ◽  
Ying He ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Vascular Function ◽  
Vascular Reactivity ◽  
Molecular Mechanisms ◽  
Rho Kinase ◽  
Mesenteric Arteries ◽  
Mineralocorticoid Receptors ◽  
Resistance Arteries ◽  
Brown Adipose

Aldosterone (aldo) plays a role in cardiovascular diseases, including hypertension and obesity. We previously demonstrated that adipocyte-derived factors regulate vascular function and cell signaling in cultured vascular smooth muscle cells. Moreover, adipocytes are able to produce aldo, which influences vascular reactivity. Plasma levels of aldo are positively correlated with obesity and hypertension. However, the pathophysiological role of aldo and mineralocorticoid receptors (MR) in adipose tissue and its interactions with the vasculature remains elusive. In our study, we investigated molecular mechanisms whereby activation of MR, in adipocytes, leads to release of vascular reactive factors and regulation of vascular tone, using a conditional transgenic mouse model that overexpresses MR only in the adipocytes. Vascular reactivity of resistance mesenteric arteries to acetylcholine (Ach), sodium nitroprusside and phenylephrine (Phe), in the absence or presence of fat conditioned medium (Fcm) from control and adipocyte overexpressing MR (DT) mice, was performed by myography. In basal conditions, endothelial dysfunction was not observed in DT or control mice. However, in the presence of Fcm from DT mice, relaxation to Ach was impaired in control mice (Ach 10 -6 M: 77.5±9.6% no Fcm vs. 49.8±7.5% Fcm, p<0.05), an effect blocked by N-acetyl-cysteine (anti-oxidant) (Ach 10 -6 M: 82.2±6.6%). Resistance arteries from DT mice had decreased Phe-induced contraction, compared to control mice (Phe 10 -5 M: 2.7±0.2 mN/mm CT vs. 1.7±0.2 mN/mm DT, p<0.05). Phosphorylation of ezrin, a marker of Rho kinase activation, measured by immunoblotting, was decreased in white and brown adipose tissues of DT (CT: 3.1±0.7 vs. DT: 0.6±0.1, arbitrary units, p<0.05). In conclusion, MR in adipocytes may play an important role in the regulation of vascular function, and may be involved in vascular oxidative stress. MR in adipocytes is also important to the anti-contractile properties of the adipose tissue through downregulation of Rho kinase signaling. Our study identiy novel mechanisms linking vascular and adipose biology through adipocyte MRs.

scholarly journals Central administration of TRV027 improves baroreflex sensitivity and vascular reactivity in spontaneously hypertensive rats

2018 ◽  
Vol 132 (14) ◽  
pp. 1513-1527 ◽  
Author(s):  
Alynne Carvalho-Galvão ◽  
Blessing Ogunlade ◽  
Jiaxi Xu ◽  
Cristiane R.A. Silva-Alves ◽  
Leônidas G. Mendes-Júnior ◽  
...  
Keyword(s):  
Vascular Function ◽  
Baroreflex Sensitivity ◽  
Vascular Reactivity ◽  
Mesenteric Arteries ◽  
Control Group ◽  
Ang Ii ◽  
Central Administration ◽  
Spontaneously Hypertensive ◽  
Wistar Kyoto

TRV027 is a biased agonist for the Angiotensin (Ang)-II type 1 receptor (AT1R), able to recruit β-arrestin 2 independently of G-proteins activation. β-arrestin activation in the central nervous system (CNS) was suggested to oppose the effects of Ang-II. The present study evaluates the effect of central infusion of TRV027 on arterial pressure (AP), autonomic function, baroreflex sensitivity (BRS), and peripheral vascular reactivity. Spontaneously hypertensive (SH) and Wistar Kyoto (WKY) rats were treated with TRV027 for 14 days (20 ng/h) delivered to the lateral ventricle via osmotic minipumps. Mechanistic studies were performed in HEK293T cells co-transfected with AT1R and Ang converting enzyme type 2 (ACE2) treated with TRV027 (100 nM) or Ang-II (100 nM). TRV027 infusion in SH rats (SHR) reduced AP (~20 mmHg, P<0.05), sympathetic vasomotor activity (ΔMAP = −47.2 ± 2.8 compared with −64 ± 5.1 mmHg, P<0.05) and low-frequency (LF) oscillations of AP (1.7 ± 0.2 compared with 5.8 ± 0.4 mmHg, P<0.05) compared with the SHR control group. TRV027 also increased vagal tone, improved BRS, reduced the reactivity of mesenteric arteries to Ang-II and increased vascular sensitivity to phenylephrine (Phe), acetylcholine, (ACh), and sodium nitroprusside (SNP). In vitro, TRV027 prevented the Ang-II-induced up-regulation of ADAM17 and in contrast with Ang-II, had no effects on ACE2 activity and expression levels. Furthermore, TRV027 induced lesser interactions between AT1R and ACE2 compared with Ang-II. Together, these data suggest that due to its biased activity for the β-arrestin pathway, TRV027 has beneficial effects within the CNS on hypertension, autonomic and vascular function, possibly through preserving ACE2 compensatory activity in neurones.

scholarly journals Obesity Induces Artery-Specific Alterations: Evaluation of Vascular Function and Inflammatory and Smooth Muscle Phenotypic Markers

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Antonio Garcia Soares ◽  
Maria Helena Catelli de Carvalho ◽  
Eliana Akamine
Keyword(s):  
Smooth Muscle ◽  
Mrna Expression ◽  
Vascular Function ◽  
Vascular Reactivity ◽  
Mesenteric Arteries ◽  
Collagen Deposition ◽  
Obese Mice ◽  
Phenotypic Markers ◽  
Expression Of Genes ◽  
The Impact

Vascular alterations are expected to occur in obese individuals but the impact of obesity could be different depending on the artery type. We aimed to evaluate the obesity effects on the relaxing and contractile responses and inflammatory and smooth muscle (SM) phenotypic markers in two vascular beds. Obesity was induced in C57Bl/6 mice by 16-week high-fat diet and vascular reactivity, mRNA expression of inflammatory and SM phenotypic markers, and collagen deposition were evaluated in small mesenteric arteries (SMA) and thoracic aorta (TA). Endothelium-dependent relaxation in SMA and TA was not modified by obesity. In contrast, contraction induced by depolarization and contractile agonists was reduced in SMA, whereas only contraction induced by adrenergic agonist was reduced in TA of obese mice. Obesity increased the mRNA expression of pro- and anti-inflammatory cytokines in SMA and TA. The expression of genes necessary for maintaining contractile ability was increased by obesity, but the increase was more pronounced in TA. Collagen deposition was increased in SMA, but not in TA, of obese mice. Although the endothelial function was still preserved, the SM of the two artery types was impaired by obesity, but the impairment was higher in SMA, which could be associated with SM phenotypic changes.

Abstract 36: High Salt Induces Vascular Damage Through Redox-sensitive Parp/trpm2-induced Calcium Influx And Inflammasome Modulation Without Influencing Blood Pressure

Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Rheure Alves-lopes ◽  
Karla B Neves ◽  
Augusto C Montezano ◽  
Sheon Mary ◽  
Christian Delles ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Vascular Function ◽  
Vascular Reactivity ◽  
Calcium Influx ◽  
Parp Inhibitor ◽  
High Salt ◽  
Vascular Damage ◽  
Mesenteric Arteries ◽  
Ros Generation ◽  
Tight Coupling

High salt diet (HSD) has deleterious effects on the vasculature by mechanisms not fully elucidated. We demonstrated tight coupling between Na + and Ca 2+ levels in VSMCs, where PARP-regulated TRPM2, a redox-sensitive Ca 2+ channel, plays an important role. Increased [Ca 2+ ]i also contributes to inflammasome assembly, which dysregulates vascular function. We hypothesized that HSD induces a pro-oxidant environment that contributes to PARP-induced TRPM2-activation, Ca 2+ influx and inflammasome assembly, leading to vascular damage. WKY rats were treated with 1% HSD (3 weeks). Blood pressure was assessed by tail-cuff methodology, vascular reactivity was assessed in mesenteric arteries and calcium influx, ROS generation, inflammasome and pro-contractile marker in vascular smooth muscle cells (VSMCs) in presence and absence of HS medium (HSM-140mM). HSD did not increase blood pressure (BP), but vascular contractility was exaggerated (Emax(mN): WT 10.20 ± 0.70 vs 15.17 ± 1.74), effect reversed by PARP (Emax: 11.14 ± 1.24) and TRPM2 (8-br) (Emax: 11.45 ± 1.11) inhibitors. In VSMCs, HSM behaves as a pro-oxidant agent (ROS-AU: Control 77.51 ± 2.80 vs 130.04 ± 13.89 HSM), leading to increased [Ca 2+ ]i (AUC: Control 25562.45 ± 880.48 vs 30924.8 ± 1263.85 HSM) and activation of myosin light chain (pMLC-AU: Control 99.27 ± 1.01 vs 626.87 ±71.28 HSM), by mechanisms dependent on ROS and PARP/TRPM2 activation. HSM also increased expression of inflammasome components NLRP3 (2 ΔΔCt : Control 1.20 ± 0.01 vs 1.85 ± 0.19 HSM), ASC (2 ΔΔCt : Control 1.02 ± 0.01 vs 1.49 ± 0.17 HSM) and Caspase 1 (2 ΔΔCt : Control 1.06 ± 0.03 vs 2.35 ± 0.46 HSM), which was prevented by ROS scavenger Tiron and PARP inhibitor. In conclusion, HSD-induced vascular hypercontractility involves ROS activation of PARP/TRPM2 signalling. Activation of PARP/TRPM2 was associated with increased [Ca 2+ ]i and activation of pro-contractile signaling and inflammasome assembly. Normal BP in HSD-fed rats in the presence of vascular damage suggests that ROS/PARP/TRPM2 signaling induced by salt influences vascular function independently of BP elevation. We identify a novel pathway that underlies salt-induced vascular damage and suggest a potential therapeutic role for PARP/TRPM2 inhibitors in vascular dysfunction.

scholarly journals Improved pulmonary vascular reactivity and decreased hypertrophic remodeling during nonhypercapnic acidosis in experimental pulmonary hypertension

2012 ◽  
Vol 302 (9) ◽  
pp. L875-L890 ◽  
Author(s):  
Helen Christou ◽  
Ossama M. Reslan ◽  
Virak Mam ◽  
Alain F. Tanbe ◽  
Sally H. Vitali ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Vascular Function ◽  
Vascular Reactivity ◽  
Ex Vivo ◽  
Systolic Pressure ◽  
Mesenteric Arteries ◽  
Hypoxic Exposure ◽  
Sprague Dawley ◽  
Vsmc Proliferation

Pulmonary hypertension (PH) is characterized by pulmonary arteriolar remodeling with excessive pulmonary vascular smooth muscle cell (VSMC) proliferation. This results in decreased responsiveness of pulmonary circulation to vasodilator therapies. We have shown that extracellular acidosis inhibits VSMC proliferation and migration in vitro. Here we tested whether induction of nonhypercapnic acidosis in vivo ameliorates PH and the underlying pulmonary vascular remodeling and dysfunction. Adult male Sprague-Dawley rats were exposed to hypoxia (8.5% O2) for 2 wk, or injected subcutaneously with monocrotaline (MCT, 60 mg/kg) to develop PH. Acidosis was induced with NH4Cl (1.5%) in the drinking water 5 days prior to and during the 2 wk of hypoxic exposure (prevention protocol), or after MCT injection from day 21 to 28 (reversal protocol). Right ventricular systolic pressure (RVSP) and Fulton's index were measured, and pulmonary arteriolar remodeling was analyzed. Pulmonary and mesenteric artery contraction to phenylephrine (Phe) and high KCl, and relaxation to acetylcholine (ACh) and sodium nitroprusside (SNP) were examined ex vivo. Hypoxic and MCT-treated rats demonstrated increased RVSP, Fulton's index, and pulmonary arteriolar thickening. In pulmonary arteries of hypoxic and MCT rats there was reduced contraction to Phe and KCl and reduced vasodilation to ACh and SNP. Acidosis prevented hypoxia-induced PH, reversed MCT-induced PH, and resulted in reduction in all indexes of PH including RVSP, Fulton's index, and pulmonary arteriolar remodeling. Pulmonary artery contraction to Phe and KCl was preserved or improved, and relaxation to ACh and SNP was enhanced in NH4Cl-treated PH animals. Acidosis alone did not affect the hemodynamics or pulmonary vascular function. Phe and KCl contraction and ACh and SNP relaxation were not different in mesenteric arteries of all groups. Thus nonhypercapnic acidosis ameliorates experimental PH, attenuates pulmonary arteriolar thickening, and enhances pulmonary vascular responsiveness to vasoconstrictor and vasodilator stimuli. Together with our finding that acidosis decreases VSMC proliferation, the results are consistent with the possibility that nonhypercapnic acidosis promotes differentiation of pulmonary VSMCs to a more contractile phenotype, which may enhance the effectiveness of vasodilator therapies in PH.

Abstract 66: Altered Vascular Reactivity in Mice Overexpressing Adipocyte Mineralocorticoid Receptors - Role of Oxidative Stress and Rho Kinase

Hypertension ◽  
2013 ◽  
Vol 62 (suppl_1) ◽  
Author(s):  
Aurelie Nguyen Dinh Cat ◽  
Glaucia E Callera ◽  
Tayze T Antunes ◽  
Augusto C Montezano ◽  
Ying He ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Endothelial Dysfunction ◽  
Vascular Function ◽  
Vascular Reactivity ◽  
Vascular Dysfunction ◽  
Rho Kinase ◽  
Mesenteric Arteries ◽  
Resistance Arteries ◽  
Tissue Interactions

Aldosterone (aldo) plays a role in obesity and cardiovascular diseases, such as hypertension. We previously demonstrated that adipocyte-derived factors regulate vascular function and vascular smooth muscle cells signaling. Moreover, adipocytes express aldosterone synthase (CYP11B2) and produce aldo. The mineralocorticoid receptor (MR), which is responsible for aldo signaling, is also found in these cells, but its role in regulating adipose tissue interactions with the vasculature is unknown. In this study, we investigated mechanisms whether MR activation in adipocytes regulates vascular reactivity. Conditional transgenic mice that overexpress MR in an adipocyte-specific manner were studied. Vascular reactivity of resistance mesenteric arteries to acetylcholine (Ach), sodium nitroprusside and phenylephrine (Phe), in the absence or presence of fat conditioned medium (Fcm) from control and adipocyte overexpressing MR (MROE) mice, was performed by myography. In basal conditions, endothelial dysfunction was not observed in MROE or control (Ctr) mice. However, exposure of arteries from control mice to Fcm from MROE mice induces endothelial dysfunction (Ach 10 -6 M: 77.5±9.6% no Fcm vs. 49.8±7.5% Fcm, p<0.05), an effect blocked by N-acetyl-cysteine (an antioxidant) (Ach 10 -6 M: 82.2±6.6%). Resistance arteries from MROE mice had decreased Phe-induced contraction, compared to control mice (Phe 10 -5 M: 2.7±0.2 mN/mm Ctr vs. 1.7±0.2 mN/mm MROE, p<0.05). Rho Kinase activity, which regulates vascular contraction, is decreased in arteries and adipo tissue from MROE (mesenteric arteries, Ctr: 100±16.2% vs. MROE: 31.1±6.1%, arbitrary units, p<0.01; adipose tissue, Ctr: 100±12.6% vs. MROE: 51.3±9.3%, arbitrary units, p<0.01). In conclusion, MR in adipocytes may play an important role in the regulation of vascular function, through redox-sensitive pathways and activation of Rho kinase. Our study identifies novel mechanisms linking vascular/adipose tissue biology and aldo/MR activation, which may be particularly important in vascular dysfunction associated with hypertension and hyperaldosteronism.

scholarly journals Autophagy Is Involved in Stellate Ganglion Block Reversing Posthemorrhagic Shock Mesenteric Lymph-Mediated Vascular Hyporeactivity

2021 ◽  
Vol 12 ◽  
Author(s):  
Chen Wang ◽  
Hui-Bo Du ◽  
Zhen-Ao Zhao ◽  
Jia-Yi Zhai ◽  
Li-Min Zhang ◽  
...  
Keyword(s):  
Hemorrhagic Shock ◽  
Vascular Reactivity ◽  
Stellate Ganglion ◽  
Stellate Ganglion Block ◽  
Mesenteric Arteries ◽  
Cellular Viability ◽  
Ganglion Block ◽  
Mesenteric Lymph ◽  
Vascular Hyporeactivity

Objective: The aim of this study was to clarify the role of autophagy in stellate ganglion block (SGB) reversing posthemorrhagic shock mesenteric lymph (PHSML)-mediated vascular hyporeactivity.Methods: Hemorrhagic shock model in conscious rats was employed to observe the effects of SGB (0.2 ml of 0.25% ropivacaine hydrochloride hydrate) and autophagy inhibitor 3-methyladenine (3-MA; 30 mg/kg) on the vascular reactivity of second-order rat mesenteric arteries in vitro, while the effects of PHSML (1 ml/kg) and autophagy agonist rapamycin (Rapa, 10 mg/kg) on the beneficial effect of SGB were investigated. The cellular viability, contractility, and autophagy-related protein expressions in vascular smooth muscle cells (VSMCs) were detected following treatments of PHSML, PHSML obtained from the rats that underwent hemorrhagic shock plus SGB (PHSML-SGB), and PHSML plus 3-MA (5 mM), respectively.Results: Hemorrhagic shock significantly decreased the vascular reactivity to gradient norepinephrine (NE), which is reversed by the SGB treatment and 3-MA administration. On the contrary, PHSML intravenous infusion and Rapa administration inhibited the vascular contractile responses in rats that underwent hemorrhagic shock plus SGB treatment. PHSML treatment significantly inhibited the cellular viability and contractility in VSMCs, increased the expressions of LC3-II and Beclin 1, and decreased the expression of p62, along with opposite appearances in these indices following PHSML-SGB treatment. In addition, 3-MA counteracted the adverse roles of PHSML in these indices in VSMCs.Conclusion: SGB inhibits PHSML-mediated vascular hyporeactivity by reducing the excessive autophagy in VSMCs.

scholarly journals Hyperbaric Oxygen Therapy Alters Vascular Reactivity Independent of Elevations in ATP

2015 ◽  
Vol 4 (1) ◽  
pp. 152-159
Author(s):  
Benjamin Matthew Hake ◽  
Cole Waggener ◽  
Benjamin Eovaldi ◽  
Claude Zanetti ◽  
Francis Sylvester
Keyword(s):  
Hyperbaric Oxygen ◽  
Vascular Reactivity ◽  
Ambient Air ◽  
Mesenteric Arteries ◽  
Pharmacologic Therapy ◽  
Atp Production ◽  
Hyperbaric Treatment ◽  
Atp Levels ◽  
Underlying Mechanisms ◽  
Air Control

Hyperbaric oxygen (HBO) is a pharmacologic therapy used treat a variety of medical conditions.  The underlying mechanisms of HBOs effect on vascular reactivity are poorly understood. The purpose of this study was to record the acute effects of HBO on vascular reactivity and determine the potential role of ATP in mediating these effects.  Porcine mesenteric arteries were dissected and mounted in isolated organ baths to record changes in tension in response to potassium chloride (KCl, 15-60 mM), phenylephrine (PHE, 10-7-10-4 M), and sodium nitroprusside (SNP, 10-7-10-4 M) following a 2-hour exposure to HBO (1.75 ATA).  HBO augmented responses to KCl and PHE compared to control arteries exposed to room air or nitrogen at 1.75 ATA as well as to room air at 1 atm. When compared to the 1 ATA room air control, KCl-induced constriction was significantly increased for the HBO exposure.  Treatment with HBO also augmented vascular responses to PHE and SNP relative to nitrogen, but not ambient air. We hypothesized that HBO increased ATP production in vascular smooth muscle leading to enhanced vascular reactivity.  Consequently, ATP levels were measured in mesenteric arteries but no significant differences in ATP levels were observed regardless of hyperbaric treatment.  Direct measurements of ATPs’ effects on porcine vasculature with and without hyperbaric treatment resulted in no significant findings. These results suggest that HBO alters vascular reactivity independent of elevations in ATP.

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