Pulmonary vascular pressure effects by endothelin-1 in normoxia and chronic hypoxia: a longitudinal study

1996 ◽  
Vol 271 (6) ◽  
pp. H2246-H2253 ◽  
Author(s):  
S. Tjen-A-Looi ◽  
R. Ekman ◽  
J. Osborn ◽  
I. Keith
Keyword(s):  
Pulmonary Hypertension ◽  
Ventricular Hypertrophy ◽  
Pressure Effects ◽  
Blood Levels ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Calcitonin Gene ◽  
Eta Receptor ◽  
Pulmonary Arterial

The role of endothelin (ET)-1 in pulmonary arterial pressure (Ppa) homeostasis and hypoxia-induced pulmonary hypertension was examined. ET-1 was chronically infused (2 and 4 pmol.kg-1.min-1) into the pulmonary circulation of male Sprague-Dawley rats for 3, 7, and 14 days while they were exposed to normoxia or hypobaric hypoxia (inspired O2 fraction 10%). The role of endogenous ET was examined by infusion of ET antiserum (ET-AS; 0.25 and 0.5 microliter.rat-1.h-1; cross-reacting with ET-1, -2, and -3) or the ETA-receptor blocker BQ-123 (10 pmol.kg-1.min-1). ET-1 (4 pmol) increased Ppa at 3 and 7 days in normoxia and hypoxia and was ineffective at 14 days, probably from ETA-receptor downregulation. BQ-123 blunted the hypoxic Ppa rise at all times, confirming a role for ETA receptors. ET-AS (0.5 microliter) was mostly ineffective but exacerbated hypoxic Ppa at 14 days, in contrast to BQ-123, suggesting that a different ET receptor could be involved. ET-1 infusion (2 pmol) caused right ventricular hypertrophy (RVH) in normoxia and exacerbated RVH in hypoxia, whereas BQ-123 and ET-AS (0.25 microliter) reduced hypoxic RVH. In conclusion, endogenous ET-1 plays a role in hypoxia-induced pulmonary hypertension and RVH by augmenting the level of hypoxic response. ET-1 also affects hematocrit and may reduce blood levels of the vasodilator calcitonin gene-related peptide.

scholarly journals Lodenafil treatment in the monocrotaline model of pulmonary hypertension in rats

2014 ◽  
Vol 40 (4) ◽  
pp. 421-424 ◽  
Author(s):  
Igor Bastos Polonio ◽  
Milena Marques Pagliareli Acencio ◽  
Rogério Pazetti ◽  
Francine Maria de Almeida ◽  
Bárbara Soares da Silva ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Experimental Model ◽  
Ventricular Hypertrophy ◽  
Right Heart Catheterization ◽  
Heart Catheterization ◽  
Sprague Dawley ◽  
Control Groups ◽  
Right Heart ◽  
Sprague Dawley Rats ◽  
And Control

We assessed the effects of lodenafil on hemodynamics and inflammation in the rat model of monocrotaline-induced pulmonary hypertension (PH). Thirty male Sprague-Dawley rats were randomly divided into three groups: control; monocrotaline (experimental model); and lodenafil (experimental model followed by lodenafil treatment, p.o., 5 mg/kg daily for 28 days) Mean pulmonary artery pressure (mPAP) was obtained by right heart catheterization. We investigated right ventricular hypertrophy (RVH) and IL-1 levels in lung fragments. The number of cases of RVH was significantly higher in the monocrotaline group than in the lodenafil and control groups, as were mPAP and IL-1 levels. We conclude that lodenafil can prevent monocrotaline-induced PH, RVH, and inflammation.

Reduction of chronic hypoxic pulmonary hypertension in the rat by beta-aminopropionitrile

1984 ◽  
Vol 57 (6) ◽  
pp. 1760-1766 ◽  
Author(s):  
J. S. Kerr ◽  
D. J. Riley ◽  
M. M. Frank ◽  
R. L. Trelstad ◽  
H. M. Frankel
Keyword(s):  
Pulmonary Hypertension ◽  
Left Ventricle ◽  
Right Ventricular ◽  
Ventricular Hypertrophy ◽  
Main Pulmonary Artery ◽  
Hydroxyproline Content ◽  
Sprague Dawley ◽  
Hypoxic Pulmonary Hypertension ◽  
Sprague Dawley Rats ◽  
Collagen Accumulation

We administered antifibrotic agent beta-aminopropionitrile (BAPN) to rats exposed to 10% O2-90% N2 for 3 wk to prevent excess vascular collagen accumulation. Groups of Sprague-Dawley rats studied were air breathing, hypoxic, and hypoxic treated with BAPN, 150 mg/kg twice daily intraperitoneally. After the 3-wk period, we measured mean right ventricular pressure (RVP), the ratio of weight of right ventricle to left ventricle plus septum (RV/LV + S), and hydroxyproline content of the main pulmonary artery (PA) trunk. Hypoxia increased RVP from 14 to 29 mmHg; RVP was 21 mmHg in hypoxic BAPN-treated animals. Hypoxia increased the RV/LV + S ratio from 0.28 to 0.41; the ratio was 0.32 in hypoxic BAPN-treated animals. Hypoxia increased PA hydroxyproline from 20 to 239 micrograms/artery; hydroxyproline was 179 micrograms/artery in hypoxic BAPN-treated animals. Thus BAPN prevented pulmonary hypertension, right ventricular hypertrophy, and excess vascular collagen produced by hypoxia. We conclude that vascular collagen contributes to the maintenance of chronic hypoxic pulmonary hypertension.

scholarly journals Curcumin Improves Pulmonary Hypertension Rats by Regulating Mitochondrial Function

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Jing Chen ◽  
Wen Jiang ◽  
Fei Zhu ◽  
Qiong Wang ◽  
Haiyan Yang ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Mitochondrial Function ◽  
Vascular Remodeling ◽  
Control Group ◽  
Sprague Dawley ◽  
Pulmonary Vascular Remodeling ◽  
Sprague Dawley Rats ◽  
Pulmonary Arterial ◽  
Toxicological Mechanism ◽  
And Function

Objective. To investigate the role of curcumin in regulating pathogenesis of pulmonary arterial smooth muscle cells (PASMCs) derived from pulmonary arterial hypertension (PAH) model. Methods. Male Sprague Dawley rats were injected with monocrotaline (MCT) to establish the PAH experimental model. The rats were divided into control group, MCT group, and curcumin group. At the end of the study, hemodynamic data were measured to determine pulmonary hypertension. Proliferation ability of PASMCs, a remodeling indicator of pulmonary artery and right ventricle, was detected. In addition, the morphology and function of mitochondria, antiglycolysis and antiproliferation pathways, and genes were also analyzed. Results. Curcumin may function by reversing MCT-mediated pulmonary vascular remodeling in rats. Curcumin effectively improved pulmonary vascular remodeling, promoted PASMC apoptosis, and protected mitochondrial function. In addition, curcumin treatment suppressed the PI3K/AKT pathway in PASMCs and regulated the expression of antiproliferative genes. Conclusion. Curcumin can improve energy metabolism and reverse the process of PAHS. However, there were side effects of curcumin in MCT-induced rats, suggesting that the dosage should be treated with caution and its toxicological mechanism should be further studied and evaluated.

Treatment with 5-HT potentiates development of pulmonary hypertension in chronically hypoxic rats

1997 ◽  
Vol 272 (3) ◽  
pp. H1173-H1181 ◽  
Author(s):  
S. Eddahibi ◽  
B. Raffestin ◽  
I. Pham ◽  
J. M. Launay ◽  
P. Aegerter ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Ventricular Hypertrophy ◽  
Potential Role ◽  
Pressor Response ◽  
Acute Hypoxia ◽  
Synthesis Inhibitor ◽  
Pulmonary Arterial ◽  
Isolated Lungs ◽  
Dose Dependent

The aim of this study was to investigate the potential role of 5-hydroxytryptamine (5-HT) on development of pulmonary hypertension during chronic exposure to mild (15% O2) and severe (10% O2) hypoxia. In isolated lungs from normoxic rats preconstricted with U-46619, 5-HT (10(-12)-10(-8) M) induced dose-dependent vasodilation (n = 6), which was suppressed by the NO synthesis inhibitor nitro-L-arginine methyl ester (L-NAME, 10(-4) M, n = 5) and reduced by the 5-HT3-receptor antagonist MDL-7222 (10(-5) M, n = 6). The vasoconstriction that was observed with higher concentrations of 5-HT (10(-7)-10(-4) M) was inhibited by ketanserin (10(-5) M) and methiothepin (10(-5) M, n = 6 each). The vasodilator response to 5-HT was suppressed in lungs from rats exposed to 10% O2 but not 15% O2 (n = 6 each). In conscious rats, intravenous administration of 5-HT potentiated the pulmonary pressor response to acute hypoxia (10% O2, n = 5), an effect that remained unchanged after pretreatment with a 5-HT1 and a 5-HT2 antagonist (n = 4) but was attenuated after treatment with the cyclooxygenase inhibitor meclofenamate (n = 4). Treatment with 5-HT (5 nmol/h i.v. by osmotic pumps) for 2 wk in rats simultaneously exposed to 10% O2 increased pulmonary arterial pressure, right ventricular hypertrophy, and muscularization of pulmonary vessels in comparison with their hypoxic controls (n = 12 each). No changes occurred in 15% O2 hypoxic rats (n = 12 each). The present findings show that 5-HT potentiates development of pulmonary hypertension in rats exposed to chronic hypoxia.

Sensory nerve- and neuropeptide-mediated relaxation responses in airways of Sprague-Dawley rats

1995 ◽  
Vol 78 (5) ◽  
pp. 1679-1687 ◽  
Author(s):  
J. L. Szarek ◽  
N. L. Stewart ◽  
B. Spurlock ◽  
C. Schneider
Keyword(s):  
Sensory Nerve ◽  
Electrical Field Stimulation ◽  
Sensory Nerves ◽  
Adrenergic Blockade ◽  
Sprague Dawley ◽  
Mechanically Ventilated ◽  
Sprague Dawley Rats ◽  
Calcitonin Gene ◽  
Relaxation Responses

We examined the role of sensory nerves in mediating nonadrenergic inhibitory responses in airway segments isolated from male Sprague-Dawley rats. In the presence of adrenergic blockade, capsaicin (Cap; 1 microM) elicited marked relaxation responses in isolated bronchi precontracted with bethanechol (Beth). Cap-induced inhibitory responses were unaffected by tetrodotoxin (TTX), were attenuated by incubation of the airway with indomethacin (Indo), phosphoramidon, or RP-67580, but were abolished by previous exposure of the airway to Cap and by denuding the epithelium. Substance P (SP; 1 microM), neurokinins A and B (1 microM), and calcitonin gene-related peptide (0.1 microM) relaxed Beth-contracted airway segments to a similar extent. The SP-induced responses were unaffected by adrenergic blockade or by pretreatment with either TTX, phosphoramidon, or Cap, but were attenuated by RP-67580 and abolished by Indo and by denuding the epithelium. In anesthetized mechanically ventilated rats, Cap (50 and 100 micrograms/kg i.v.) elicited a dose-dependent reversal of the increase in lung resistance induced by an infusion of Beth. The Cap-induced bronchodilation was unaffected by pretreatment with propranolol alone or in combination with hexamethonium. SP (44 nmol/kg iv) also evoked bronchodilatory responses in intact animals, which were unaffected by propranolol and hexamethonium but were abolished by treatment of the animals with Indo. Electrical-field stimulation (EFS) evoked nonadrenergic noncholinergic relaxation responses in contracted airway segments. These EFS-induced inhibitory responses were markedly attenuated by treatment of the airway segment with TTX, Cap, or RP-67580. We conclude that neuropeptides released from Cap-sensitive sensory nerves have potent inhibitory effects in rat airways that are mediated, in part, by activation of neurokonin NK1 receptors on epithelium and subsequent release of an inhibitory prostaglandin(s).

Notoginsenoside R1 Attenuates Hypoxia and Hypercapnia-Induced Vasoconstriction in Isolated Rat Pulmonary Arterial Rings by Reducing the Expression of ERK

2014 ◽  
Vol 42 (04) ◽  
pp. 799-816 ◽  
Author(s):  
Yixiao Xu ◽  
Lina Lin ◽  
Lanlan Tang ◽  
Mengxiao Zheng ◽  
Yingchun Ma ◽  
...  
Keyword(s):  
Pulmonary Arteries ◽  
Panax Notoginseng ◽  
Underlying Mechanism ◽  
Sprague Dawley ◽  
Third Order ◽  
Pulmonary Vasoconstriction ◽  
Sprague Dawley Rats ◽  
Specific Objective ◽  
Pulmonary Arterial

Pulmonary arterial hypertension (PAH) is a disease of the small pulmonary arteries characterized by increased vascular resistance. Pulmonary vasoconstriction has been proven to play a pivotal role in PAH. We have previously hypothesized that Panax notoginseng saponins (PNS) might attenuate hypoxia–hypercapnia-induced pulmonary vasoconstriction. The specific objective of the present study was to investigate the role of notoginsenoside R1, a main ingredient of PNS, in this process and the possible underlying mechanism. The third order pulmonary rings from the Sprague-Dawley rats were treated with different concentrations of notoginsenoside R1 (8, 40, and 100 mg/L, respectively) both before and during the conditions of hypercapnia and hypoxia. Contractile force changes in the rings were detected and the optimal concentration (8 mg/L) was selected. Furthermore, an ERK inhibitor, U0126, was applied to the rings. In addition, pulmonary arterial smooth muscle cells (PASMCs) were cultured under hypoxic and hypercapnic conditions, and notoginsenoside R1 was administered to detect the changes induced by ERK1/2. The results revealed biphasic vasoconstriction in rings under hypoxic and hypercapnic conditions. It is hypothesized that the observed attenuation of vasoconstriction and the production of vasodilation could have been induced by notoginsenoside R1. This effect was found to be significantly reinforced by U0126 (p < 0.05 or p < 0.01). ERK expression in the PASMCs under hypoxic and hypercapnic conditions was significantly activated (p < 0.05 or p < 0.01) and the observed activation was attenuated by notoginsenoside R1 (p < 0.05 or p < 0.01). Our findings strongly support the significant role of notoginsenoside R1 in the inhibition of hypoxia–hypercapnia-induced vasoconstriction by the ERK pathway.

scholarly journals EXPRESS: Endothelial-derived eNAMPT drives EndMT and preclinical PH: Rescue by an eNAMPT-neutralizing mAb

2021 ◽  
pp. 204589402110597
Author(s):  
Mohamed Ahmed ◽  
Nahla Zaghloul ◽  
Prisca Zimmerman ◽  
Nancy G. Casanova ◽  
Xiaoguang Sun ◽  
...  
Keyword(s):  
Vascular Remodeling ◽  
Unmet Need ◽  
Sprague Dawley ◽  
Mesenchymal Transition ◽  
Molecular Pattern ◽  
Sprague Dawley Rats ◽  
Sequencing Studies ◽  
Pulmonary Arterial ◽  
Nicotinamide Phosphoribosyl Transferase

Rationale: Pharmacologic interventions to halt/reverse the vascular remodeling and right ventricular (RV) dysfunction in pulmonary arterial hypertension (PAH) remains an unmet need. We previously demonstrated extracellular nicotinamide phosphoribosyl-transferase (eNAMPT) as a DAMP (damage-associated molecular pattern protein) contributing to PAH pathobiology via TLR4 ligation. We examined the role of endothe-lial cell (EC)-specific eNAMPT in experimental PH and an eNAMPT-neutralizing mAb as a therapeutic strategy to reverse established PH. Methods: Hemodynam-ic/echocardiographic measurements and tissue analyses were performed in Sprague Dawley rats exposed to 10% hypoxia/Sugen (3 weeks) followed by return to normoxia and weekly intraperitoneal delivery of the eNAMPT mAb (1 mg/kg). WT C57BL/6J mice and conditional EC-cNAMPTec-/- mice were exposed to 10% hypoxia (3 weeks). Bio-chemical and RNA sequencing studies were performed on rat PH lung tissues and human PAH PBMCs. Results: Hypoxia/Sugen-exposed rats exhibited multiple indices of severe PH (RVSP, Fulton index), including severe vascular remodeling, compared to control rats. PH severity indices and plasma levels of eNAMPT, IL-6, and TNF-a were all significantly attenuated by eNAMPT mAb neutralization. Compared to hypoxia-exposed WT mice, cNAMPTec-/- KO mice exhibited significantly reduced PH severity and evidence of EC to mesenchymal transition (EndMT). Finally, biochemical and RNAseq analyses revealed eNAMPT mAb-mediated rectification of dysregulated inflammatory signaling pathways (TLR/NF-κB, MAP kinase, Akt/mTOR) and EndMT in rat PH lung tissues and human PAH PBMCs. Conclusions: These studies underscore EC-derived eNAMPT as a key contributor to PAH pathobiology and support the eNAMPT/TLR4 inflammatory pathway as a highly druggable therapeutic target to reduce PH severity and reverse PAH.

scholarly journals Acute Effects of Vardenafil on Pulmonary Artery Responsiveness in Pulmonary Hypertension

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Edibe Karasu-Minareci ◽  
Irem Hicran Ozbudak ◽  
Gulay Ozbilim ◽  
Gulay Sadan
Keyword(s):  
Pulmonary Hypertension ◽  
Pulmonary Arteries ◽  
Dependent Manner ◽  
Sprague Dawley ◽  
Response Curves ◽  
Concentration Dependent Manner ◽  
Sprague Dawley Rats ◽  
Pathway Activation ◽  
Pulmonary Arterial ◽  
Phosphodiesterase Type

Phosphodiesterase type-5 (PDE-5) inhibitors are novel and important options for the treatment of pulmonary arterial hypertension (PAH). Therefore, we aimed to examine effects of vardenafil, a PDE-5 inhibitor, on the pulmonary arteries isolated from rats with monocrotaline- (MCT-) induced pulmonary hypertension. MCT (60 mg/kg) or its vehicle was administered by a single intraperitoneal injection to 6-week-old male Sprague Dawley rats. Rats were sacrificed 21 days after MCT injection, and the main pulmonary arteries were isolated and then mounted in 20 mL organ baths. Concentration-response curves for vardenafil (10−10–10−5 M) were constructed in phenylephrine- (Phe-) precontracted rings. PAH caused marked rightward shift in the curves to vardenafil whereas maximal responses were not affected. Inhibition of NO synthase (L-NAME, 10−4 M) or guanylyl cyclase (ODQ, 10−5 M) caused similar attenuation in responses evoked by vardenafil. Moreover, contraction responses induced by CaCl2(3×10−5–3×10−2 M) were significantly reduced in concentration-dependent manner by vardenafil. In conclusion, vardenafil induced pulmonary vasodilatation via inhibition of extracellular calcium entry in addition to NO-cGMP pathway activation. These results provide evidence that impaired arterial relaxation in PAH can be prevented by vardenafil. Thus, vardenafil represents a valuable therapeutic approach in PAH besides other PDE-5 inhibitors.

Effects of Nitric Oxide on Monocrotaline Induced Right Ventricular Hypertrophy and Lung Mast Cell Hyperplasia in Rats

1998 ◽  
Vol 4 (S2) ◽  
pp. 1072-1073
Author(s):  
Kuen-Shan Hung ◽  
William H. Duncan
Keyword(s):  
Nitric Oxide ◽  
Right Ventricular ◽  
Ventricular Hypertrophy ◽  
Right Ventricular Hypertrophy ◽  
Sprague Dawley ◽  
Cell Hyperplasia ◽  
Arterial Walls ◽  
Sprague Dawley Rats ◽  
Pulmonary Arterial ◽  
Mast Cell Hyperplasia

Monocrotaline (M) induces pulmonary hypertension (PH) characterized by increased pulmonary arterial pressure, thickened pulmonary arterial walls, and right ventricular hypertrophy (RVH). In addition, numerous mast cells (MC) have been localized in M treated rats and these cells may have a role in causing PH and other lung injury because of their content of serotonin, which is a vasoconstrictor. Nitric oxide (NO) is a vasodilator that has been used in treatments of human patients and experimental animals with PH. The purpose of this study is to determine if NO inhalation can prevent or reverse RVH or MC accumulation induced by M.Adult male Sprague-Dawley rats were divided into 5 groups (C, M3, MN3, M5, MN5). Group C served as controls without treatments. Groups M3 and M5 received one single subcutaneous injection of M (80mg/kg BW) and were sacrificed at 3 weeks (M3) or 5 weeks (M5) after injection.

Three-week neonatal hypoxia reduces blood CGRP and causes persistent pulmonary hypertension in rats

2000 ◽  
Vol 279 (4) ◽  
pp. H1571-H1578 ◽  
Author(s):  
I. M. Keith ◽  
S. Tjen-A-Looi ◽  
H. Kraiczi ◽  
R. Ekman
Keyword(s):  
Pulmonary Hypertension ◽  
Ventricular Hypertrophy ◽  
Pulmonary Arterial Pressure ◽  
Pulmonary Arteries ◽  
Left Ventricular ◽  
Persistent Pulmonary Hypertension ◽  
Perinatal Exposure ◽  
Calcitonin Gene ◽  
Potent Vasodilator ◽  
Pulmonary Arterial

To increase understanding of persistent pulmonary hypertension, we examined chronic pulmonary effects of hypoxia at birth and their relationships with immunoreactive levels of the potent vasodilator, calcitonin gene-related peptide (CGRP). Rats were born in 10% hypobaric hypoxia, where they remained for 1–2 days, or in 15% hypoxia, where they remained for 21 days. All were then reared in normoxia for 3 mo followed by reexposure to 10% hypoxia for 7 days (H→H) or continued normoxia (H→N); age-matched normoxic rats were hypoxic for the last 7 days (N→H) or normoxic throughout (N→N). Results are as follows. Pulmonary arterial pressure (PPA) in 10% H→N rats was normal at the end of the experiment (13 wk), but in rats reexposed to hypoxia (H→H), pressure rose to 19% above N→H controls. In 15% H→N rats, PPA remained high, similar to that of N→H rats, and increased further by 40% on reexposure (H→H). Medial thickness of small pulmonary arteries in 10% H→H rats also increased by 40% over N→H controls and was equally high in 15% H→N and H→H rats. In N→H rats from both experiments, right ventricular hypertrophy index (RVH) was increased after hypoxia at 15–16 wk. Also, in the 15% study, RVH remained elevated in H→N rats and increased in H→H rats by 19% above N→H controls. Blood CGRP was reduced by neonate and adult hypoxia, and hypoxic reexposure (H→H) further lowered blood CGRP in the 15% but not 10% study. Declining left ventricular blood CGRP correlated highly with logarithmically increasing PPA in the 15% study ( r = −0.81, P = 0.000). In conclusion, 1) short perinatal exposure to 10% O2 exacerbated pulmonary hypertension with hypoxia later in life, 2) 15% O2 at birth and for 21 days caused persistent pulmonary hypertension and exacerbation with reexposure, and 3) PPA correlated highly with declining blood CGRP levels in the 15% study.

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