Proteinases as Mediators of the Disturbance of Pulmonary Vascular Permeability in Sepsis, Polytrauma, and ARDS

1992 ◽  
pp. 67-74 ◽  
Author(s):  
H. Neuhof ◽  
H. Fritz
Keyword(s):  
Vascular Permeability ◽  
Pulmonary Vascular Permeability

Elevated intracranial pressure increases pulmonary vascular permeability to protein

1989 ◽  
Vol 67 (3) ◽  
pp. 1185-1191 ◽  
Author(s):  
M. D. McClellan ◽  
I. M. Dauber ◽  
J. V. Weil
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Intracranial Pressure ◽  
Pulmonary Edema ◽  
Vascular Permeability ◽  
Elevated Intracranial Pressure ◽  
Hemodynamic Changes ◽  
Pulmonary Vascular Permeability ◽  
Pulmonary Arterial ◽  
Protein Permeability

The syndrome of neurogenic pulmonary edema raises the question of whether there are neurological influences on pulmonary vascular permeability. Previous experimental models commonly produced severe hemodynamic alterations, complicating the distinction of increased permeability from increased hydrostatic forces in the formation of the pulmonary edema. Accordingly, we employed a milder central nervous system insult and measured the pulmonary vascular protein extravasation rate, which is a sensitive and specific indicator of altered protein permeability. After elevating intracranial pressure via cisternal saline infusion in anesthetized dogs, we used a dual isotope method to measure the protein leak index. This elevated intracranial pressure resulted in a nearly three-fold rise in the protein leak index (54.1 +/- 7.5 vs. 20.2 +/- 0.9). This central nervous system insult was associated with only mild increases in pulmonary arterial pressures and cardiac output. However, when we reproduced these hemodynamic changes with left atrial balloon inflation or isoproterenol infusion, we observed no effect on the protein leak index compared with control. Although the pulmonary arterial wedge pressure with intracranial pressure remained <10 mmHg, increases in the extravascular lung water were demonstrated. The results suggest the existence of neurological influences on pulmonary vascular protein permeability. We conclude that neurological insults result in increase pulmonary vascular permeability to protein and subsequent edema formation, which could not be accounted for by hemodynamic changes alone.

scholarly journals Bacillus anthracis lethal toxin, but not edema toxin, increases pulmonary artery pressure and permeability in isolated perfused rat lungs

2019 ◽  
Vol 316 (5) ◽  
pp. H1076-H1090 ◽  
Author(s):  
Xizhong Cui ◽  
Wanying Xu ◽  
Pranita Neupane ◽  
Andie Weiser-Schlesinger ◽  
Ray Weng ◽  
...  
Keyword(s):  
Pulmonary Artery ◽  
Bacillus Anthracis ◽  
Vascular Permeability ◽  
Pulmonary Artery Pressure ◽  
Lethal Toxin ◽  
Rat Lung ◽  
Fluid Accumulation ◽  
Pulmonary Vascular Permeability ◽  
Artery Pressure ◽  
Edema Toxin

Although lethal toxin (LT) and edema toxin (ET) contribute to lethality during Bacillus anthracis infection, whether they increase vascular permeability and the extravascular fluid accumulation characterizing this infection is unclear. We employed an isolated perfused Sprague-Dawley rat lung model to investigate LT and ET effects on pulmonary vascular permeability. Lungs ( n ≥ 6 per experimental group) were isolated, ventilated, suspended from a force transducer, and perfused. Lung weight and pulmonary artery (Ppa) and left atrial pressures were measured over 4 h, after which pulmonary capillary filtration coefficients (Kf.c) and lung wet-to-dry weight ratios (W/D) were determined. When compared with controls, LT increased Ppa over 4 h and Kf.c and W/D at 4 h ( P < 0.0001). ET decreased Ppa in a significant trend ( P = 0.09) but did not significantly alter Kf.c or W/D ( P ≥ 0.29). Edema toxin actually blocked LT increases in Ppa but not LT increases in Kf.c and W/D. When Ppa was maintained at control levels, LT still increased Kf.c and W/D ( P ≤ 0.004). Increasing the dose of each toxin five times significantly increased and a toxin-directed monoclonal antibody decreased the effects of each toxin ( P ≤ 0.05). Two rho-kinase inhibitors (GSK269962 and Y27632) decreased LT increases in Ppa ( P ≤ 0.02) but actually increased Kf.c and W/D in LT and control lungs ( P ≤ 0.05). A vascular endothelial growth factor receptor inhibitor (ZM323881) had no significant effect ( P ≥ 0.63) with LT. Thus, LT but not ET can increase pulmonary vascular permeability independent of increased Ppa and could contribute to pulmonary fluid accumulation during anthrax infection. However, pulmonary vascular dilation with ET could disrupt protective hypoxic vasoconstriction. NEW & NOTEWORTHY The most important findings from the present study are that Bacillus anthracis lethal toxin increases pulmonary artery pressure and pulmonary permeability independently in the isolated rat lung, whereas edema toxin decreases the former and does not increase permeability. Each effect could be a basis for organ dysfunction in patients with this lethal infection. These findings further support the need for adjunctive therapies that limit the effects of both toxins during infection.

Cortactin Depletion Increases Pulmonary Vascular Permeability In Vitro And In Vivo

2011 ◽  
Author(s):  
Patrick Belvitch ◽  
Mary E. Brown ◽  
Sara M. Camp ◽  
Anjali Desai ◽  
Liliana Moreno-Vinasco ◽  
...  
Keyword(s):  
Vascular Permeability ◽  
Pulmonary Vascular Permeability

Granulocytes mediate the increase in pulmonary vascular permeability after thrombin embolism

1983 ◽  
Vol 54 (6) ◽  
pp. 1489-1495 ◽  
Author(s):  
M. V. Tahamont ◽  
A. B. Malik
Keyword(s):  
Vascular Permeability ◽  
Control Group ◽  
Base Line ◽  
Protein Ratio ◽  
Pulmonary Vascular Permeability ◽  
Pulmonary Capillary ◽  
Cellular Factors ◽  
Pulmonary Embolization ◽  
Lung Lymph

We examined the effect of pulmonary embolization with microthrombi on the lung vascular permeability to proteins and the role of platelets and granulocytes as putative cellular factors in mediating the alterations in permeability. Anesthetized artificially ventilated sheep were prepared with lung lymph fistulas. Pulmonary embolization was induced using thrombin. Pulmonary vascular resistance (PVR) was increased approximately threefold from baseline. Pulmonary lymph flow (Qlym) increased 2 h after thrombin, but the lymph-to-plasma protein ratio (L/P) did not change significantly from base line. Raising the pulmonary capillary pressure (Pc) by inflating a left atrial balloon produced a large increase in Qlym but no change in L/P, indicating a permeability-increasing effect of thrombin. Reduction of platelet count with antiplatelet serum before thrombin also produced an increase in Qlym without a change in L/P. Raising Pc in this group resulted in changes comparable with those in the control group, i.e., increased Qlym without a change in L/P. In contrast to both control and platelet-depleted groups, reduction of the granulocyte count with hydroxyurea did not affect Qlym or L/P after thrombin. Raising Pc in this group increased Qlym but decreased L/P, indicating normal capillary sieving of proteins. Therefore embolization of pulmonary vessels with microthrombi increases pulmonary vascular permeability, and the increase is mediated by granulocytes.

scholarly journals Expression of urocortin in rat lung and its effect on pulmonary vascular permeability

2006 ◽  
Vol 189 (1) ◽  
pp. 167-178 ◽  
Author(s):  
Yuqing Wu ◽  
Yinyan Xu ◽  
Hong Zhou ◽  
Jin Tao ◽  
Shengnan Li
Keyword(s):  
Receptor Antagonist ◽  
Vascular Permeability ◽  
Alveolar Epithelium ◽  
Bronchial Epithelium ◽  
Rat Lung ◽  
Pulmonary Vascular Permeability ◽  
Peripheral Tissues ◽  
The Central Nervous System ◽  
Hematoxylin And Eosin ◽  
Lung Vascular Permeability

Urocortin (UCN), a newly identified, 40-amino-acid, corticotropin-releasing hormone (CRH) structurally related peptide, has been demonstrated to be expressed in the central nervous system and many peripheral tissues of rats and man. This study aimed to investigate the expression profile of UCN in rat lung and the effect of UCN on lung vascular permeability. The expression of UCN mRNA was detected by reverse transcriptase PCR (RT–PCR). UCN peptide was measured by immunohistochemistry and Western blot analysis. We found that both UCN mRNA and peptide were obviously expressed in rat lung. Immunohistochemistry results showed that UCN peptide is mainly expressed in bronchial epithelium mucosa and alveolar epithelium. We also found that rats receiving inhalation aerosol of UCN had a significant elevation of lung vascular permeability compared with rats receiving vehicle and ovalbumin (OVA) by the Evans blue (EB) technique. UCN aerosol inhalation resulted in obvious pulmonary congestion and edema observed under light microscope by hematoxylin and eosin (HE) staining. The nonselective peptide CRH receptor antagonist astressin markedly reduced lung vascular permeability triggered by UCN. Enhanced pulmonary vascular permeability induced by UCN was markedly inhibited by pretreatment with the mast-cell stabilizer cromolyn and histamine-1 (H1) receptor antagonist azelastine respectively, but not by the leukotriene receptor antagonist montelukast. In summary, in the present study, we demonstrated for the first time that UCN is expressed in rat lung and contributes to an increase in lung vascular permeability through activation of CRH receptors. Mast cells and histamine may be involved in this effect of UCN. Peripherally produced UCN in lung may act as an autocrine and paracrine proinflammatory factor.

scholarly journals Activated protein C attenuates endotoxin-induced pulmonary vascular injury by inhibiting activated leukocytes in rats

Blood ◽  
1996 ◽  
Vol 87 (2) ◽  
pp. 642-647 ◽  
Author(s):  
K Murakami ◽  
K Okajima ◽  
M Uchiba ◽  
M Johno ◽  
T Nakagaki ◽  
...  
Keyword(s):  
Vascular Permeability ◽  
Vascular Injury ◽  
Active Site ◽  
Protein C ◽  
Anticoagulant Activity ◽  
Activated Protein C ◽  
Myeloperoxidase Activity ◽  
Granulocyte Elastase ◽  
Pulmonary Vascular Permeability ◽  
Elastase Inhibitor

We investigated the effect of activated protein C (APC) on lipopolysaccharide (LPS)-induced pulmonary vascular injury in rats to investigate the possible usefulness of APC as a treatment for adult respiratory distress syndrome. Intravenously administered LPS (5 mg/kg) significantly increased pulmonary vascular permeability. APC prevented the LPS-induced increase in pulmonary vascular permeability observed at 6 hours. Heparin plus antithrombin III (ATIII) and active site-blocked factor Xa (DEGR-Xa), a selective inhibitor of thrombin generation, inhibited LPS-induced coagulopathy but did not prevent LPS-induced pulmonary vascular injury. LPS-induced pulmonary vascular injury was significantly attenuated in rats with nitrogen mustard-induced leukocytopenia and in rats treated with ONO-5046, a potent granulocyte elastase inhibitor. Administration of LPS also increased pulmonary accumulation of leukocytes, as evaluated by measurement of myeloperoxidase activity in the lungs. APC significantly reduced LPS- induced increases in pulmonary accumulation of leukocytes at 1 hour. Neither ATIII plus heparin nor DEGR-Xa inhibited leukocyte accumulation. Active site-blocked APC (DIP-APC) prevented neither the LPS-induced pulmonary accumulation of leukocytes nor the LPS-induced increase in pulmonary vascular permeability. These results suggest that the mechanism of APC inhibition of LPS-induced pulmonary vascular injury was independent of its anticoagulant activity and was related to its ability to inhibit accumulation of leukocytes. In addition, these findings suggest that the serine protease activity of APC may be essential to its inhibitory effect on LPS-induced pulmonary accumulation of leukocytes and subsequent pulmonary vascular injury.

Effects of transient pulmonary hypertension on pulmonary vascular permeability

1983 ◽  
Vol 55 (3) ◽  
pp. 983-989 ◽  
Author(s):  
F. L. Minnear ◽  
P. S. Barie ◽  
A. B. Malik
Keyword(s):  
Pulmonary Edema ◽  
Vascular Permeability ◽  
Left Atrial ◽  
Lymph Flow ◽  
Balloon Inflation ◽  
Lung Water ◽  
Lung Weight ◽  
Pulmonary Vascular Permeability ◽  
Airway Edema ◽  
Vascular Surface

The effects of a transient increase in pulmonary microvascular pressure (Pmv) on pulmonary fluid and protein exchange were studied in anesthetized sheep in which pulmonary lymph was collected. Pmv was increased to 30-40 mmHg for 15-30 min in 18 sheep by either an intra-aortic injection of norepinephrine (NE) or a rapid inflation of a left atrial balloon. NE injection produced sustained two- to threefold increases in pulmonary lymph flow and protein flux, whereas rapid balloon inflation transiently elevated lymph flow even though Pmv increased to similar levels with both methods. The sustained increases with NE were not due to an increase in vascular permeability but probably the result of a persistent increase in vascular surface area. In three additional animals, Pmv was increased to over 50 mmHg for 15-30 min. In these animals, lymph flow increased only by 49%, but airway edema fluid was present. The ratio of extravascular lung water to bloodless dry lung weight was 5.77 +/- 0.13 as compared with 4.30 +/- 0.11 in sheep subjected to Pmv less than 50 mmHg and to 4.08 +/- 0.19 for controls. These findings indicate that high pressure-induced pulmonary edema depends on a threshold Pmv around 50 mmHg. A combination of high capillary pressure and impaired lymphatic flow may be the bases for the development of neurogenic and catecholamine-induced pulmonary edema.

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