Hypoxia enhances unilateral lung injury by increasing blood flow to the injured lung

1987 ◽  
Vol 63 (6) ◽  
pp. 2516-2523 ◽  
Author(s):  
K. Takeda ◽  
M. J. Knapp ◽  
W. G. Wolfe ◽  
J. D. Crapo
Keyword(s):  
Blood Flow ◽  
Lung Injury ◽  
Left Lung ◽  
Weight Ratio ◽  
Normal Lung ◽  
Lung Edema ◽  
Lung Weight ◽  
Edema Formation ◽  
Concomitant Decrease ◽  
Injured Lung

We hypothesized that in unilateral lung injury, bilateral hypoxic ventilation would induce vasoconstriction in the normal lung, redirect blood flow to the injured lung, and cause enhanced edema formation. Unilateral left lung injury was induced by intrabronchial instillation of 1.5 ml/kg of 0.1 N HCl. After HCl injury, blood flow to the injured left lung decreased progressively from 0.70 +/- 0.04 to 0.37 +/- 0.05 l/min and percent of flow to the injured left lung (QL/QT) decreased from 37.7 +/- 2.2 to 23.6 +/- 2.2% at 240 min. Exposure to hypoxia (12% O2) for three 10-min episodes did not affect QL/QT in normal animals, but after unilateral HCl injury, it caused blood flow to the injured left lung to increase significantly. A concomitant decrease in blood flow occurred to the noninjured right lung, resulting in a significant increase in QL/QT. The enhanced blood flow to the injured lung was associated with a significant increase in the wet-to-dry lung weight ratio in the dependent regions of the injured lung. These findings demonstrate that in unilateral HCl-induced lung injury, transient hypoxia can enhance blood flow to the areas of injury and increase lung edema formation.

scholarly journals Effects of Roflumilast, a Phosphodiesterase-4 Inhibitor, on the Lung Functions in a Saline Lavage-Induced Model of Acute Lung Injury

2017 ◽  
pp. S237-S245 ◽  
Author(s):  
P. KOSUTOVA ◽  
P. MIKOLKA ◽  
M. KOLOMAZNIK ◽  
S. REZAKOVA ◽  
A. CALKOVSKA ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Weight Ratio ◽  
Lung Compliance ◽  
Pde4 Inhibitor ◽  
Lung Edema ◽  
Lung Weight ◽  
Edema Formation ◽  
Phosphodiesterase 4 ◽  
Respiratory Parameters

Acute lung injury (ALI) is associated with deterioration of alveolar-capillary lining and transmigration and activation of inflammatory cells. Whereas a selective phosphodiesterase-4 (PDE4) inhibitor roflumilast has exerted potent anti-inflammatory properties, this study evaluated if its intravenous delivery can influence inflammation, edema formation, and respiratory parameters in rabbits with a lavage-induced model of ALI. ALI was induced by repetitive saline lung lavage (30 ml/kg). Animals were divided into 3 groups: ALI without therapy (ALI), ALI treated with roflumilast i.v. (1 mg/kg; ALI+Rofl), and healthy ventilated controls (Control), and were ventilated for following 4 h. Respiratory parameters (blood gases, ventilatory pressures, lung compliance, oxygenation indexes etc.) were measured and calculated regularly. At the end of experiment, animals were overdosed by anesthetics. Total and differential counts of cells in bronchoalveolar lavage fluid (BAL) were estimated microscopically. Lung edema was expressed as wet/dry lung weight ratio. Treatment with roflumilast reduced leak of cells (P<0.01), particularly of neutrophils (P<0.001), into the lung, decreased lung edema formation (P<0.01), and improved respiratory parameters. Concluding, the results indicate a future potential of PDE4 inhibitors also in the therapy of ALI.

Leukotriene B4 induces lung injury in the rabbit: role of neutrophils and effect of indomethacin

1993 ◽  
Vol 74 (5) ◽  
pp. 2174-2179 ◽  
Author(s):  
K. Yoshimura ◽  
S. Nakagawa ◽  
S. Koyama ◽  
T. Kobayashi ◽  
T. Homma
Keyword(s):  
Arachidonic Acid ◽  
Lung Injury ◽  
Weight Ratio ◽  
Leukotriene B4 ◽  
Arachidonic Acid Metabolism ◽  
Microvascular Permeability ◽  
Lung Edema ◽  
Lung Weight ◽  
Fluid Filtration ◽  
Pmn Leukocytes

The effects of exogenous leukotriene B4 (LTB4) on the pulmonary microvascular permeability and the roles of polymorphonuclear (PMN) leukocytes and the cyclooxygenase products of arachidonic acid in the microvascular response to LTB4 in the isolated non-blood-perfused rabbit lungs were studied. Microvascular permeability and lung edema were evaluated by use of the fluid filtration coefficient (Kf) and the wet-to-dry lung weight ratio (W/D ratio), respectively. Pulmonary capillary pressure was estimated by the double occlusion technique. We studied five groups of lungs: lungs were given 1) both PMN leukocytes and a bolus injection of LTB4 (5 micrograms, n = 6), 2) LTB4 alone (n = 5), 3) PMN leukocytes alone (n = 5), 4) control vehicles (n = 5), or 5) indomethacin (40 micrograms/ml) before PMN leukocytes and LTB4 (n = 6). We observed that LTB4 increased Kf and W/D ratio in the presence of PMN leukocytes in the perfusate without affecting the pulmonary arterial and capillary pressures. Neither LTB4 alone nor PMN leukocytes alone produced changes in Kf and W/D ratio. Indomethacin failed to inhibit the LTB4-induced increases in Kf and W/D ratio. These results suggest that LTB4 produces lung injury that is dependent on PMN leukocytes but not on the cyclooxygenase pathway of arachidonic acid metabolism.

scholarly journals Intravenous Dexamethasone Attenuated Inflammation and Influenced Apoptosis of Lung Cells in an Experimental Model of Acute Lung Injury

2016 ◽  
pp. S663-S672 ◽  
Author(s):  
P. KOSUTOVA ◽  
P. MIKOLKA ◽  
S. BALENTOVA ◽  
M. ADAMKOV ◽  
M. KOLOMAZNIK ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Caspase 3 ◽  
Diffuse Alveolar Damage ◽  
Weight Ratio ◽  
Dry Weight ◽  
Inflammatory Cells ◽  
Lavage Fluid ◽  
Lung Edema ◽  
Edema Formation

Acute lung injury (ALI) is characterized by diffuse alveolar damage, inflammation, and transmigration and activation of inflammatory cells. This study evaluated if intravenous dexamethasone can influence lung inflammation and apoptosis in lavage-induced ALI. ALI was induced in rabbits by repetitive saline lung lavage (30 ml/kg, 9±3-times). Animals were divided into 3 groups: ALI without therapy (ALI), ALI treated with dexamethasone i.v. (0.5 mg/kg, Dexamed; ALI+DEX), and healthy non-ventilated controls (Control). After following 5 h of ventilation, ALI animals were overdosed by anesthetics. Total and differential counts of cells in bronchoalveolar lavage fluid (BAL) were estimated. Lung edema was expressed as wet/dry weight ratio. Concentrations of IL-1ß, IL-8, esRAGE, S1PR3 in the lung were analyzed by ELISA methods. In right lung, apoptotic cells were evaluated by TUNEL assay and caspase-3 immunohistochemically. Dexamethasone showed a trend to improve lung functions and histopathological changes, reduced leak of neutrophils (P<0.001) into the lung, decreased concentrations of pro-inflammatory IL-1β (P<0.05) and marker of lung injury esRAGE (P<0.05), lung edema formation (P<0.05), and lung apoptotic index (P<0.01), but increased immunoreactivity of caspase-3 in the lung (P<0.001). Considering the action of dexamethasone on respiratory parameters and lung injury, the results indicate potential of this therapy in ALI.

scholarly journals EphA2 receptor mediates increased vascular permeability in lung injury due to viral infection and hypoxia

2009 ◽  
Vol 297 (5) ◽  
pp. L856-L863 ◽  
Author(s):  
Melissa A. Cercone ◽  
William Schroeder ◽  
Stacey Schomberg ◽  
Todd C. Carpenter
Keyword(s):  
Endothelial Cells ◽  
Lung Injury ◽  
Tyrosine Kinases ◽  
Normal Lung ◽  
Vascular Leak ◽  
Edema Formation ◽  
Viral Respiratory Infection ◽  
Injured Lung ◽  
Lung Injury Model ◽  
Mrna And Protein Expression

Ephrin family receptor tyrosine kinases are mediators of angiogenesis that may also regulate endothelial barrier function in the lung. Previous work has demonstrated that stimulation of EphA ephrin receptors causes increased vascular leak in the intact lung and increased permeability in cultured endothelial cells. Whether EphA receptors are involved in the permeability changes associated with lung injury is unknown. We studied this question in young rats exposed to viral respiratory infection combined with exposure to moderate hypoxia, a previously described lung injury model. We found that the EphA2 receptor is expressed in normal lung and that EphA2 expression is markedly upregulated in the lungs of hypoxic infected (HV) rats compared with normal control animals. Immunohistochemistry showed increased EphA2 expression principally in areas of edematous alveolar septae. In HV rats, EphA2 antagonism with either the soluble decoy receptor EphA2/Fc or with monoclonal anti-EphA2 antibody reduced albumin extravasation and histological evidence of edema formation ( P < 0.01). Vascular leak in HV rats is mediated in large part by increased lung endothelin (ET) levels. In HV rats, ET receptor antagonism with bosentan resulted in reduced EphA2 mRNA and protein expression ( P < 0.01). Experiments with cultured rat lung microvascular endothelial cells demonstrated that ET increases endothelial EphA2 expression. These results suggest that EphA2 expression is increased in lung injury, contributes to vascular leak in the injured lung, and is regulated in endothelial cells by ET. EphA2 may be a previously unrecognized contributor to the pathophysiology of lung injury.

Lung edema formation following inhalation injury: role of the bronchial blood flow

1991 ◽  
Vol 71 (2) ◽  
pp. 727-734 ◽  
Author(s):  
S. Abdi ◽  
D. N. Herndon ◽  
L. D. Traber ◽  
K. D. Ashley ◽  
J. C. Stothert ◽  
...  
Keyword(s):  
Blood Flow ◽  
Bronchial Artery ◽  
Weight Ratio ◽  
Dry Weight ◽  
Inhalation Injury ◽  
Smoke Inhalation ◽  
Lung Edema ◽  
Edema Formation ◽  
Group 2 ◽  
Group 1

We investigated the contribution of the bronchial blood flow to the lung lymph flow (QL) and lung edema formation after inhalation injury in sheep (n = 18). The animals were equally divided into three groups and chronically prepared by implantation of cardiopulmonary catheters and a flow probe on the common bronchial artery. Groups 1 and 2 sheep were insufflated with 48 breaths of cotton smoke while group 3 received only room air. Just before injury, the bronchial artery of group 2 animals was occluded. The occlusion was maintained for the duration of the 24-h study period. At the end of the investigation, samples of lung were taken for determination of blood-free wet weight-to-dry weight ratio (W/D). Inhalation injury induced a sevenfold increase in QL in group 1 (7 +/- 1 to 50 +/- 9 ml/h; P less than 0.05) but only a threefold increase in group 2 (10 +/- 2 to 28 +/- 7 ml/h; P less than 0.05). The mean W/D value of group 1 animals was 23% higher than that of group 2 (5.1 +/- 0.4 vs. 3.9 +/- 0.2; P less than 0.05). Our data suggest that the bronchial circulation contributes to edema formation in the lung that is often seen after the acute lung injury with smoke inhalation.

scholarly journals 17β-Estradiol Protects the Lung against Acute Injury: Possible Mediation by Vasoactive Intestinal Polypeptide

Endocrinology ◽  
2011 ◽  
Vol 152 (12) ◽  
pp. 4729-4737 ◽  
Author(s):  
Sayyed A. Hamidi ◽  
Kathleen G. Dickman ◽  
Hasan Berisha ◽  
Sami I. Said
Keyword(s):  
Lung Injury ◽  
Oxidant Stress ◽  
Weight Ratio ◽  
Lavage Fluid ◽  
Experimental Models ◽  
Acute Injury ◽  
Normal Lung ◽  
Lung Weight ◽  
Lung Protection ◽  
17Β Estradiol

Beyond their classical role as a class of female sex hormones, estrogens (e.g. 17β-estradiol) exert important biological actions, both protective and undesirable. We have investigated the ability of estradiol to protect the lung in three models of acute injury induced by 1) oxidant stress due to the herbicide paraquat; 2) excitotoxicity, caused by glutamate agonist N-methyl-d-aspartate; and 3) acute alveolar anoxia. We also assessed the role of estrogen receptors (ER) ERα and ERβ and the neuropeptide vasoactive intestinal peptide (VIP) in mediating this protection. Isolated guinea pig or rat lungs were perfused in situ at constant flow and mechanically ventilated. The onset and severity of lung injury were monitored by increases in pulmonary arterial and airway pressures, wet/dry lung weight ratio, and bronchoalveolar lavage fluid protein content. Estradiol was infused into the pulmonary circulation, beginning 10 min before induction of injury and continued for 60–90 min. Lung injury was marked by significant increases in the above measurements, with paraquat producing the most severe, and excitotoxicity the least severe, injury. Estradiol significantly attenuated the injury in each model. Both ER were constitutively expressed and immunohistochemically demonstrable in normal lung, and their selective agonists reduced anoxic injury, the only model in which they were tested. As it protected against injury, estradiol rapidly and significantly stimulated VIP mRNA expression in rat lung. Estradiol attenuated acute lung injury in three experimental models while stimulating VIP gene expression, a known mechanism of lung protection. The up-regulated VIP expression could have partially mediated the protection by estrogen.

Recombinant human VEGF treatment transiently increases lung edema but enhances lung structure after neonatal hyperoxia

2006 ◽  
Vol 291 (5) ◽  
pp. L1068-L1078 ◽  
Author(s):  
Anette M. Kunig ◽  
Vivek Balasubramaniam ◽  
Neil E. Markham ◽  
Gregory Seedorf ◽  
Jason Gien ◽  
...  
Keyword(s):  
Lung Injury ◽  
Pulmonary Edema ◽  
Recovery Period ◽  
Weight Ratio ◽  
Lung Edema ◽  
Sprague Dawley ◽  
Lung Weight ◽  
Lung Structure ◽  
Neonatal Hyperoxia ◽  
Enos Protein

Recent studies suggest that VEGF may worsen pulmonary edema during acute lung injury (ALI), but, paradoxically, impaired VEGF signaling contributes to decreased lung growth during recovery from ALI due to neonatal hyperoxia. To examine the diverse roles of VEGF in the pathogenesis of and recovery from hyperoxia-induced ALI, we hypothesized that exogenous recombinant human VEGF (rhVEGF) treatment during early neonatal hyperoxic lung injury may increase pulmonary edema but would improve late lung structure during recovery. Sprague-Dawley rat pups were placed in a hyperoxia chamber (inspired O2 fraction 0.9) for postnatal days 2–14. Pups were randomized to daily intramuscular injections of rhVEGF165 (20 μg/kg) or saline (controls). On postnatal day 14, rats were placed in room air for a 7-day recovery period. At postnatal days 3, 14, and 21, rats were killed for studies, which included body weight and wet-to-dry lung weight ratio, morphometric analysis [including radial alveolar counts (RAC), mean linear intercepts (MLI), and vessel density], and lung endothelial NO synthase (eNOS) protein content by Western blot analysis. Compared with room air controls, hyperoxia increased pulmonary edema by histology and wet-to-dry lung weight ratios at postnatal day 3, which resolved by day 14. Although treatment with rhVEGF did not increase edema in control rats, rhVEGF increased wet-to-dry weight ratios in hyperoxia-exposed rats at postnatal days 3 and 14 ( P < 0.01). Compared with room air controls, hyperoxia decreased RAC and increased MLI at postnatal days 14 and 21. Treatment with VEGF resulted in increased RAC by 181% and decreased MLI by 55% on postnatal day 14 in the hyperoxia group ( P < 0.01). On postnatal day 21, RAC was increased by 176% and MLI was decreased by 58% in the hyperoxia group treated with VEGF. rhVEGF treatment during hyperoxia increased eNOS protein on postnatal day 3 by threefold ( P < 0.05). We conclude that rhVEGF treatment during hyperoxia-induced ALI transiently increases pulmonary edema but improves lung structure during late recovery. We speculate that VEGF has diverse roles in hyperoxia-induced neonatal lung injury, contributing to lung edema during the acute stage of ALI but promoting repair of the lung during recovery.

Endothelin-1 potentiates leukotoxin-induced edematous lung injury

1995 ◽  
Vol 79 (4) ◽  
pp. 1106-1111 ◽  
Author(s):  
T. Ishizaki ◽  
K. Shigemori ◽  
T. Nakai ◽  
S. Miyabo ◽  
M. Hayakawa ◽  
...  
Keyword(s):  
Lactate Dehydrogenase ◽  
Lung Injury ◽  
Venous Pressure ◽  
Weight Ratio ◽  
Lung Edema ◽  
Lung Weight ◽  
Lactate Dehydrogenase Activity ◽  
Endothelin 1 ◽  
Endothelin A Receptor ◽  
Endothelin A

We tested the hypothesis that leukotoxin (Lx), a cytochrome P-450-dependent linoleate product of leukocytes, can stimulate the release of endothelin-1 (ET-1) from the lung and further that exogenous ET-1 synergizes with Lx to produce edematous lung injury. In isolated rat lungs perfused with Earle's balanced salt solution, Lx (10 mumol) alone caused lung edema and increased the perfusate and lung tissue ET-1 levels. The combination of ET-1 (5 nM) and Lx (5 mumol), at concentrations that by themselves did not increase wet lung weight, significantly increased wet lung weight, wet-to-dry lung weight ratio, as well as the lung effluent lactate dehydrogenase activity. Pretreatment with BQ-123 (5 x 10(-6) M), an endothelin A receptor antagonist that significantly attenuated the ET-1 (5 nM)-induced increase in pulmonary arterial pressure (Ppa) and pulmonary capillary pressure (Ppc), suppressed the edematous lung injury generated by the combination of ET-1 and Lx, suggesting that the edema-enhancing effect of ET-1 in Lx-treated lungs occurred through endothelin A receptor-dependent elevation of Ppa and Ppc. Elevation of the pulmonary venous pressure in Lx-treated lungs (13.5 cmH2O) mimicked the effect of ET-1 on Ppa and Ppc and produced a degree of lung edema that was comparable to that after combined ET-1 + Lx treatment but without increase in the perfusate lactate dehydrogenase. These data support the idea that ET-1 and Lx promote lung edema in a synergistic fashion.

Unilateral acute lung injury induced by ethchlorvynol in anesthetized dogs

1984 ◽  
Vol 56 (5) ◽  
pp. 1252-1259 ◽  
Author(s):  
A. H. Stephenson ◽  
R. S. Sprague ◽  
T. E. Dahms ◽  
A. J. Lonigro
Keyword(s):  
Blood Flow ◽  
Acute Lung Injury ◽  
Lung Injury ◽  
Airway Pressure ◽  
Left Lung ◽  
Arterial Occlusion ◽  
Peak Airway Pressure ◽  
Lung Water ◽  
Injured Lung ◽  
Anesthetized Dogs

Ethchlorvynol (ECV) was used to induce unilateral acute lung injury in anesthetized dogs. Measurements of extravascular thermal volume by double-indicator (thermal-dye) dilution with and without left main pulmonary arterial occlusion permitted sequential estimates of extravascular lung water (EVLW) for each lung. Determinations of EVLW by thermal-dye and gravimetric methods were highly correlated (r = 0.80). ECV (9–15 mg/kg) administered into the right pulmonary circulation produced progressive increases in right lung EVLW, which by 120 min post-ECV was increased 152 +/- 22% (SE) over control (P less than 0.001). Left lung EVLW remained unchanged. Similarly, right, but not left, peak airway pressure was increased. Thermal dilution, coupled with electromagnetic methods, permitted estimates of blood flow to each lung. Despite redistribution of flow to the uninjured lung, systemic PO2 decreased (P less than 0.001) and venous admixture increased (P less than 0.05), suggesting impaired matching of ventilation and perfusion. In summary, introduction of ECV into one lung produced unilateral acute lung injury. EVLW increased solely in the injured lung as did peak airway pressure. Although there was a partial redistribution of blood flow away from the injured lung to the uninjured one, it was apparently inadequate to prevent impaired oxygenation of the blood.

Site of pulmonary edema after unilateral microembolization

1979 ◽  
Vol 47 (3) ◽  
pp. 556-560 ◽  
Author(s):  
B. C. Lee ◽  
H. van der Zee ◽  
A. B. Malik
Keyword(s):  
Pulmonary Edema ◽  
Left Lung ◽  
Weight Ratio ◽  
Normal Lung ◽  
Similar Degree ◽  
Base Line ◽  
Lung Water ◽  
Lung Weight ◽  
Right Pulmonary Artery ◽  
The Right

The effect of unilateral pulmonary microembolization on regional lung extravascular fluid accumulation was determined in dogs. Embolization was produced by injecting 100-micrometer-diam glass beads (0.25 g/kg) into the right pulmonary artery. After embolization of one lung, pulmonary arterial pressure (Ppa) and pulmonary vascular resistance increased (P less than 0.05) from base-line values of 11.7 +/- 1.3 to 17.9 +/- 1.3 Torr and of 3.4 +/- 0.5 to 5.5 +/- 0.5 Torr/(1/min). Blood flow to embolized lung measured with labeled microspheres decreased from 104.2 +/- 24.9 to 35.2 +/- 9.2 ml/min.g bloodless lung after embolization, whereas flow to the normal lung increased from 43.1 +/- 5.6 to 71.2 +/- 19.2 ml/min.g bloodless lung. Extravascular lung water-to-bloodless dry lung weight ratio (W/D) of 4.97 +/- 0.32 was greater (P less than 0.001) in the embolized lung than the value of 3.34 +/- 0.15 in nonembolized lung. In six dogs pretreated with 500 U/kg of heparin, a similar degree of duration of embolization and similar hemodynamic changes did not result in significant differences in W/D (3.88 +/- 0.18 in right lung vs. 3.02 +/- 0.53 in the left lung), and the right lung ratio was less (P less than 0.05) than the value in the heparinized dogs, suggesting that humoral mechanisms contribute to the genesis of pulmonary edema after regional embolization. Therefore, unilateral embolization leads to a greater increase in extravascular content in the embolized lung than in the nonembolized lung. Because Ppa was in the normal range after embolization, regional pulmonary edema may be due partly to the local release of factors that increase lung vascular permeability.

Sign in / Sign up

Export Citation Format

Share Document