Thromboxane synthase inhibition and cardiopulmonary function during endotoxemia in sheep

1991 ◽  
Vol 71 (4) ◽  
pp. 1376-1381 ◽  
Author(s):  
K. Fujioka ◽  
K. Sugi ◽  
T. Isago ◽  
J. T. Flynn ◽  
L. D. Traber ◽  
...  
Keyword(s):  
Cardiac Index ◽  
Systolic Pressure ◽  
Lymph Flow ◽  
Thromboxane Synthase ◽  
Thromboxane Synthase Inhibitor ◽  
Dimension Analysis ◽  
Pulmonary Arterial ◽  
Synthase Inhibitor ◽  
Lung Lymph ◽  
Lung Lymph Flow

We studied the cardiopulmonary response to endotoxin (lipopolysaccharide, LPS) in sheep with and without the administration of a thromboxane synthase inhibitor, OKY-046. The animals were instrumented for crystalographic dimension analysis of the left ventricle (LV) and for measurement of LV, aortic, left atrial, and pulmonary arterial pressures and cardiac index, as well as lung lymph flow. They received 1.0 micrograms/kg of Escherichia coli LPS with (n = 8) and without (n = 8) OKY-046 (10 mg/kg bolus, then 10 micrograms.kg-1.min-1). OKY-046 prevented the increase of pulmonary arterial pressure and the decrease of cardiac index that occurred during the early phase of endotoxemia. Between 8 and 12 h after LPS, cardiac index increased from 6.8 +/- 0.7 to 8.9 +/- 0.51.min-1.m-2. Concomitantly, the end-systolic pressure-diameter relationship (ESPDR, sensitive myocardial contractility index) significantly decreased from 14.7 +/- 0.6 to 7.7 +/- 0.7. Other indexes of the LV contractility (+dP/dtmax) were also reduced. OKY-046 prevented the decreases of ESPDR and +dP/dtmax. OKY-046 also attenuated the increased lung lymph flow changes seen with LPS.

Effect of interstitial edema on lung lymph flow in goats in the absence of filtration

1992 ◽  
Vol 72 (3) ◽  
pp. 1142-1148 ◽  
Author(s):  
K. Kambara ◽  
K. E. Longworth ◽  
V. B. Serikov ◽  
N. C. Staub
Keyword(s):  
Lymph Flow ◽  
Alveolar Wall ◽  
Half Time ◽  
Interstitial Edema ◽  
Lung Water ◽  
Pulmonary Arterial ◽  
The Mean ◽  
Lung Lymph ◽  
Normal Lungs ◽  
Lung Lymph Flow

We tested the effect of interstitial edema on lung lymph flow when no filtration occurred. In 16 anesthetized open-thorax ventilated supine goats, we set pulmonary arterial and left atrial pressures to nearly zero and measured lymph flow for 3 h from six lungs without edema and ten with edema. Lymph flow decreased exponentially in all experiments as soon as filtration ceased. In the normal lungs the mean half time of the lymph flow decrease was 12.7 +/- 4.8 (SD) min, which was significantly shorter (P less than 0.05) than the 29.1 +/- 14.8 min half time in the edematous lungs. When ventilation was stopped, lymph flow in the edematous lungs decreased as rapidly as in the normal lungs. The total quantity of lymph after filtration ceased was 2.7 +/- 0.8 ml in normal lungs and 9.5 +/- 6.3 ml in edematous lungs, even though extravascular lung water was doubled in the latter (8.4 +/- 2.4 vs. 3.3 +/- 0.4 g/g dry lung, P less than 0.01). Thus the maximum possible clearance of the interstitial edema liquid by the lymphatics was 6.3 +/- 4.8%. When we restarted pulmonary blood flow after 1–2 h in four additional goats, lymph flow recovered within 30 min to the baseline level. These findings support the hypothesis that lung lymph flow originates mainly from alveolar wall perimicrovascular interstitial liquid and that the contribution of the lung lymphatic system to the clearance of interstitial edema (bronchovascular cuffs, interlobular septa) is small.

Inspiratory airway obstruction does not affect lung fluid balance in lambs

1985 ◽  
Vol 58 (4) ◽  
pp. 1314-1318 ◽  
Author(s):  
T. N. Hansen ◽  
A. L. Gest ◽  
S. Landers
Keyword(s):  
Airway Obstruction ◽  
Endotracheal Tube ◽  
Fluid Balance ◽  
Left Atrial ◽  
Lymph Flow ◽  
Lung Fluid ◽  
Lung Fluid Balance ◽  
Pulmonary Arterial ◽  
Lung Lymph ◽  
Lung Lymph Flow

The purpose of this study was to examine the effects of inspiratory airway obstruction on lung fluid balance in newborn lambs. We studied seven 2- to 4-wk-old lambs that were sedated with chloral hydrate and allowed to breathe 30–40% O2 spontaneously through an endotracheal tube. We measured lung lymph flow, lymph and plasma protein concentrations, pulmonary arterial and left atrial pressures, mean and phasic pleural pressures and airway pressures, and cardiac output during a 2-h base-line period and then during a 2- to 3-h period of inspiratory airway obstruction produced by partially occluding the inspiratory limb of a nonrebreathing valve attached to the endotracheal tube. During inspiratory airway obstruction, both pleural and airway pressures decreased 5 Torr, whereas pulmonary arterial and left atrial pressures each decreased 4 Torr. As a result, calculated filtration pressure remained unchanged. Inspiratory airway obstruction had no effect on steady-state lung lymph flow or the lymph protein concentration relative to that of plasma. We conclude that in the spontaneously breathing lamb, any decrease in interstitial pressure resulting from inspiratory airway obstruction is offset by a decrease in microvascular hydrostatic pressure so that net fluid filtration remains unchanged.

Effect of progressive exercise on lung fluid balance in sheep

1988 ◽  
Vol 64 (5) ◽  
pp. 2125-2131 ◽  
Author(s):  
J. H. Newman ◽  
B. J. Butka ◽  
R. E. Parker ◽  
R. J. Roselli
Keyword(s):  
Cardiac Output ◽  
Fluid Balance ◽  
Lymph Flow ◽  
Base Line ◽  
Lung Fluid ◽  
Lung Fluid Balance ◽  
Progressive Exercise ◽  
Pulmonary Arterial ◽  
Lung Lymph ◽  
Lung Lymph Flow

The purpose of this study is to determine the roles of cardiac output and microvascular pressure on changes in lung fluid balance during exercise in awake sheep. We studied seven sheep during progressive treadmill exercise to exhaustion (10% grade), six sheep during prolonged constant-rate exercise for 45–60 min, and five sheep during hypoxia (fraction of inspired O2 = 0.12) and hypoxic exercise. We made continuous measurements of pulmonary arterial, left atrial, and systemic arterial pressures, lung lymph flow, and cardiac output. Exercise more than doubled cardiac output and increased pulmonary arterial pressures from 19.2 +/- 1 to 34.8 +/- 3.5 (SE) cmH2O. Lung lymph flow increased rapidly fivefold during progressive exercise and returned immediately to base-line levels when exercise was stopped. Lymph-to-plasma protein concentration ratios decreased slightly but steadily. Lymph flows correlated closely with changes in cardiac output and with calculated microvascular pressures. The drop in lymph-to-plasma protein ratio during exercise suggests that microvascular pressure rises during exercise, perhaps due to increased pulmonary venous pressure. Lymph flow and protein content were unaffected by hypoxia, and hypoxia did not alter the lymph changes seen during normoxic exercise. Lung lymph flow did not immediately return to base line after prolonged exercise, suggesting hydration of the lung interstitium.

Oleic acid lung injury in sheep

1986 ◽  
Vol 60 (2) ◽  
pp. 433-440 ◽  
Author(s):  
M. Julien ◽  
J. M. Hoeffel ◽  
M. R. Flick
Keyword(s):  
Oleic Acid ◽  
Lung Injury ◽  
Pulmonary Edema ◽  
Fluid Balance ◽  
Lymph Flow ◽  
Lung Fluid ◽  
Lung Fluid Balance ◽  
Pulmonary Arterial ◽  
Lung Lymph ◽  
Lung Lymph Flow

Intravenous infusion of oleic acid into experimental animals causes acute lung injury resulting in pulmonary edema. We investigated the mechanism of oleic acid lung injury in sheep. In experiments with anesthetized and unanesthetized sheep with lung lymph fistulas, we measured pulmonary arterial and left atrial pressures, cardiac output, lung lymph flow, and lymph and plasma protein concentrations. We injured the lungs with intravenous infusions of oleic acid at doses ranging from 0.015 to 0.120 ml/kg. We found that oleic acid caused reproducible dose-related increases in pulmonary arterial pressure and pulmonary vascular resistance, arterial hypoxemia, and increased protein-rich lung lymph flow and extravascular lung water. The lung fluid balance changes were characteristic of increased permeability pulmonary edema. Infusion of the esterified fat triolein had no hemodynamic or lung fluid balance effects. Depletion of leukocytes with a nitrogen mustard or platelets with an antiplatelet serum had no effect on oleic acid lung injury. Treatment of sheep before injury with methylprednisolone 30 mg/kg or ibuprofen 12.5–15.0 mg/kg also had no effects. Unlike other well-characterized sheep lung injuries, injury caused by oleic acid does not require participation of leukocytes.

Cardiopulmonary responses to continuous administration of endotoxin

1988 ◽  
Vol 254 (5) ◽  
pp. H833-H839 ◽  
Author(s):  
D. L. Traber ◽  
H. Redl ◽  
G. Schlag ◽  
D. N. Herndon ◽  
R. Kimura ◽  
...  
Keyword(s):  
Hydrostatic Pressure ◽  
Cardiac Index ◽  
Pulmonary Artery ◽  
Pulmonary Artery Pressure ◽  
Sham Group ◽  
Peripheral Resistance ◽  
Lymph Flow ◽  
Continuous Administration ◽  
Lung Lymph ◽  
Lung Lymph Flow

The cardiopulmonary response to continuous administration of lipopolysaccharide (LPS) was studied in chronically instrumented sheep. LPS was administered in doses of 0 (sham), 6, 9, 12, and 24 ng.kg-1.h-1 for 24 h. No significant changes in the measured variables occurred in the sham group and in the 6 ng.kg-1.h-1-LPS group. With 9, 12, and 24 ng.kg-1.h-1-LPS, cardiac index rose and peripheral resistance fell to the same extent in all three groups. Lung lymph flow (QL) increased with increasing concentration of LPS. These elevations in QL occurred in the presence of only minor increases in the pulmonary artery pressure, which rose to the same extent in the 9, 12, and 24 ng.kg-1.h-1 groups. Consequently, the changes in QL were attributable to changes in fluid conductance of the pulmonary microvasculature rather than variations in hydrostatic pressure. The increase in QL correlated with a decrease in prekallikrein levels (r = 0.97), indicating that the changes in fluid conductance might have been kinin mediated.

Hypoxia and angiotensin II infusion redistribute lung blood flow in lambs

1985 ◽  
Vol 58 (3) ◽  
pp. 812-818 ◽  
Author(s):  
T. N. Hansen ◽  
A. L. Le Blanc ◽  
A. L. Gest
Keyword(s):  
Blood Flow ◽  
Angiotensin Ii ◽  
Arterial Pressure ◽  
Pulmonary Arterial Pressure ◽  
Lymph Flow ◽  
Filtration Pressure ◽  
Alveolar Hypoxia ◽  
Pulmonary Arterial ◽  
Lung Lymph ◽  
Lung Lymph Flow

To assess the effects of alveolar hypoxia and angiotensin II infusion on distribution of blood flow to the lung we performed perfusion lung scans on anesthetized mechanically ventilated lambs. Scans were obtained by injecting 1–2 mCi of technetium-labeled albumin macroaggregates as the lambs were ventilated with air, with 10–14% O2 in N2, or with air while receiving angiotensin II intravenously. We found that both alveolar hypoxia and infusion of angiotensin II increased pulmonary vascular resistance and redistributed blood flow from the mid and lower lung regions towards the upper posterior region of the lung. We assessed the effects of angiotensin II infusion on filtration pressure in six lambs by measuring the rate of lung lymph flow and the protein concentration of samples of lung lymph. We found that angiotensin II infusion increased pulmonary arterial pressure 50%, lung lymph flow 90%, and decreased the concentration of protein in lymph relative to plasma. These results are identical to those seen when filtration pressure increases during alveolar hypoxia. We conclude that alveolar hypoxia and angiotensin II infusion both increase fluid filtration in the lung by increasing filtration pressure. The increase in filtration pressure may be the result of a redistribution of blood flow in the lung with relative overperfusion of vessels in some areas and transmission of the elevated pulmonary arterial pressure to fluid-exchanging sites in those vessels.

Pulmonary and coronary endothelial effects of acute myocardial ischemia in dogs

1982 ◽  
Vol 242 (3) ◽  
pp. H337-H348
Author(s):  
M. H. Gee ◽  
J. T. Flynn ◽  
J. A. Spath
Keyword(s):  
Steady State ◽  
Lymph Flow ◽  
Flow Rates ◽  
Protein Clearance ◽  
Acute Mi ◽  
Anesthetized Dogs ◽  
Pulmonary Arterial ◽  
Lung Lymph ◽  
Lung Vascular Permeability ◽  
Lung Lymph Flow

We measured pulmonary arterial (Ppa) and left atrial (Pla) pressures, lung lymph flow rate (QL), and protein clearance in 23 anesthetized dogs with ligation (MI) dogs or sham ligation (sham-MI dogs) of a coronary artery combined with either large transient increases in Pla or moderate steady-state increases in Pla. In steady-state experiments we also collected cardiac lymph. Plasma and lymph concentrations of several prostanoids including prostacyclin (PGI2) and thromboxane B2 (TXB2) were measured. Lung lymph flow rates and protein clearances were increased in MI dogs compared with those in sham-MI dogs in experiments with transient increases in Pla. Similarly in steady-state experiments lung QL and protein clearance were increased after MI. Cardiac QL increased after MI with no change in lymph protein clearance. Lung and cardiac lymph PGI2 and plasma TXB2 concentrations increased after MI. We suggest that acute MI results in increased lung vascular permeability and that activation of formed elements in blood may be involved in mediating MI-induced vascular injury.

scholarly journals Furegrelate, a Thromboxane Synthase Inhibitor, Blunts the Development of Pulmonary Arterial Hypertension in Neonatal Piglets

2012 ◽  
Vol 2 (2) ◽  
pp. 193-200 ◽  
Author(s):  
Dinesh K. Hirenallur-S ◽  
Neil D. Detweiler ◽  
Steven T. Haworth ◽  
Jeaninne T. Leming ◽  
John B. Gordon ◽  
...  
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Thromboxane Synthase ◽  
Neonatal Piglets ◽  
Thromboxane Synthase Inhibitor ◽  
Pulmonary Arterial ◽  
Synthase Inhibitor

Potentiation of lung vascular response to endotoxin by superoxide dismutase

1985 ◽  
Vol 58 (3) ◽  
pp. 1005-1009 ◽  
Author(s):  
D. L. Traber ◽  
T. Adams ◽  
L. Sziebert ◽  
M. Stein ◽  
L. Traber
Keyword(s):  
Superoxide Dismutase ◽  
Lymph Flow ◽  
Halothane Anesthesia ◽  
Protein Ratio ◽  
Hydroxyl Ion ◽  
Before And After ◽  
Blood Neutrophils ◽  
Pulmonary Arterial ◽  
Lung Lymph ◽  
Lung Lymph Flow

We studied the effects of superoxide dismutase (SOD), an enzyme that converts superoxide into peroxide, on the cardiopulmonary response to endotoxin in sheep. Sheep (n = 18) were prepared for chronic measurement of cardiopulmonary variables, including lung lymph flow, by surgically implanting catheters under halothane anesthesia. Nine of the animals were studied before and after the administration of endotoxin (0.75 microgram/kg) with and without SOD. An additional nine animals received SOD without the lipopolysaccharide. Endotoxin produced an increase in lung lymph flow that was initially associated with a marked pulmonary arterial (PA) hypertension and reduced lymph-to-plasma protein ratio (L/P). The lymph flow remained elevated later in the response, but there was only a mild increase in PA pressure, and the L/P was normal. There was also a fall in blood neutrophils and in cardiac index. SOD increased this secondary elevation in lung lymph flow, and the corresponding L/P was greater than the preendotoxin value. The fall in neutrophil count, cardiac output, and the elevation in PA pressure seen with endotoxin were not affected by SOD. When administered in the absence of endotoxin, SOD produced no perceptible change in the cardiopulmonary and lymph values. We conclude that peroxide, hydroxyl ion, and/or other free radicals formed by the action of SOD must be responsible for a portion of the endotoxin response rather than superoxide itself.

A Comparison of Human Pulmonary Arterial and Venous Prostacyclin and Thromboxane Synthesis- Effect of a Thromboxane Synthase Inhibitor

1984 ◽  
Vol 51 (02) ◽  
pp. 257-260 ◽  
Author(s):  
A J Carter ◽  
J A Bevan ◽  
S P Hanley ◽  
W E Morgan ◽  
D R Turner
Keyword(s):  
Thoracic Surgery ◽  
Pulmonary Arteries ◽  
Significant Inhibition ◽  
Thromboxane B2 ◽  
Thromboxane Synthase ◽  
Paired Samples ◽  
Thromboxane Synthase Inhibitor ◽  
Pulmonary Arterial ◽  
Synthase Inhibitor ◽  
Arteries And Veins

SummaryThe amounts of 6-keto-prostaglandin F1α (6-keto-PGF1α) and thromboxane B2 (TxB2) produced by the endothelial surfaces of paired samples of human pulmonary arteries and veins, obtained from patients undergoing thoracic surgery, were measured. The amounts of 6-keto-PGF1α and TxB2 produced by arteries compared with veins were not different. However, both arteries and veins produced more 6-keto-PGFlα than TxB2, the ratio being approximately 7.5:1 for both. 6-keto-PGFlα synthesis by arteries was significantly correlated with that produced by veins but the relative amounts of TxB2 were not correlated. 6-keto-PGFlα synthesis was correlated with TxB2 synthesis for veins but not for arteries. 8 of the 12 arterial samples exhibited some degree of intimal fibrosis.Incubation with the thromboxane synthase inhibitor, dazoxiben, caused a significant inhibition of vascular TxB2 synthesis and a significant increase in 6-keto-PGFlα synthesis. In 3 of the 5 cases the increase in 6-keto-PGFlα was too large to be explained by the fall in TxB2.

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