Inhibition of the calcium paradox in isolated rat hearts by high perfusate sucrose concentrations

1994 ◽  
Vol 266 (5) ◽  
pp. H1729-H1737
Author(s):  
A. Omachi ◽  
R. A. Kleps ◽  
T. O. Henderson ◽  
R. J. Labotka
Keyword(s):  
Pressure Gradient ◽  
Sucrose Concentration ◽  
Choline Chloride ◽  
Weight Ratio ◽  
Dry Weight ◽  
Calcium Paradox ◽  
Oncotic Pressure ◽  
Rat Hearts ◽  
The Moment ◽  
Langendorff Hearts

If a colloid osmotic (oncotic) pressure gradient develops across the myocyte membrane during the calcium paradox, adding an oncotic agent to the perfusate should be inhibitory. After 10-min perfusion with Ca(2+)-free Krebs-Henseleit (KH) buffer under constant flow at 34 degrees C, myoglobin release was measured from Langendorff hearts reperfused with Ca(2+)-containing KH buffer. When the Ca(2+)-free medium contained 200 mM sucrose, myoglobin release was reduced to 5% of that observed in the absence of sucrose, a change that was not seen when 200 mosM NaCl, choline chloride, LiCl, or glycerol was added. Replacement of 75 mM NaCl in the perfusate with 150 mM sucrose resulted in myoglobin release values that were 4% of the control. Plots of myoglobin release against sucrose concentration under these hypertonic and isotonic conditions yielded similar though separate curves. Sucrose also inhibited increases in wet weight-to-dry weight ratio and decreases in ATP and phosphocreatine contents. These results support the hypothesis that an oncotic pressure gradient arises during the calcium paradox at the moment of increased membrane permeability and plays a major role in its development.

scholarly journals Preservation of renal endothelial integrity and reduction of renal edema by aprotinin does not preserve renal perfusion and function following experimental cardiopulmonary bypass

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Nicole A. M. Dekker ◽  
Anoek L. I. van Leeuwen ◽  
Matijs van Meurs ◽  
Jill Moser ◽  
Jeannette E. Pankras ◽  
...  
Keyword(s):  
Cardiopulmonary Bypass ◽  
Renal Injury ◽  
Weight Ratio ◽  
Kidney Injury ◽  
Dry Weight ◽  
Renal Perfusion ◽  
Plasma Creatinine ◽  
Microcirculatory Perfusion ◽  
Neutrophil Influx ◽  
Endothelial Integrity

Abstract Background Acute kidney injury is a severe complication following cardiopulmonary bypass (CPB) and is associated with capillary leakage and microcirculatory perfusion disturbances. CPB-induced thrombin release results in capillary hyperpermeability via activation of protease-activated receptor 1 (PAR1). We investigated whether aprotinin, which is thought to prevent thrombin from activating PAR1, preserves renal endothelial structure, reduces renal edema and preserves renal perfusion and reduces renal injury following CPB. Methods Rats were subjected to CPB after treatment with 33.000 KIU/kg aprotinin (n = 15) or PBS (n = 15) as control. A secondary dose of 33.000 KIU/kg aprotinin was given 60 min after initiation of CPB. Cremaster and renal microcirculatory perfusion were assessed using intravital microscopy and contrast echography before CPB and 10 and 60 min after weaning from CPB. Renal edema was determined by wet/dry weight ratio and renal endothelial structure by electron microscopy. Renal PAR1 gene and protein expression and markers of renal injury were determined. Results CPB reduced cremaster microcirculatory perfusion by 2.5-fold (15 (10–16) to 6 (2–10) perfused microvessels, p < 0.0001) and renal perfusion by 1.6-fold (202 (67–599) to 129 (31–292) au/sec, p = 0.03) in control animals. Both did not restore 60 min post-CPB. This was paralleled by increased plasma creatinine (p < 0.01), neutrophil gelatinase-associated lipocalin (NGAL; p = 0.003) and kidney injury molecule-1 (KIM-1; p < 0.01). Aprotinin treatment preserved cremaster microcirculatory perfusion following CPB (12 (7–15) vs. 6 (2–10) perfused microvessels, p = 0.002), but not renal perfusion (96 (35–313) vs. 129 (31–292) au/s, p > 0.9) compared to untreated rats. Aprotinin treatment reduced endothelial gap formation (0.5 ± 0.5 vs. 3.1 ± 1.4 gaps, p < 0.0001), kidney wet/dry weight ratio (4.6 ± 0.2 vs. 4.4 ± 0.2, p = 0.046), and fluid requirements (3.9 ± 3.3 vs. 7.5 ± 3.0 ml, p = 0.006) compared to untreated rats. In addition, aprotinin treatment reduced tubulointerstitial neutrophil influx by 1.7-fold compared to untreated rats (30.7 ± 22.1 vs. 53.2 ± 17.2 neutrophil influx/section, p = 0.009). No differences were observed in renal PAR1 expression and plasma creatinine, NGAL or KIM-1 between groups. Conclusions Aprotinin did not improve renal perfusion nor reduce renal injury during the first hour following experimental CPB despite preservation of renal endothelial integrity and reduction of renal edema.

scholarly journals Testing the potential of LEDs to enhance growth and quality characteristics of Salvia fruticosa

2019 ◽  
Vol 46 (No. 2) ◽  
pp. 98-106 ◽  
Author(s):  
Filippos Bantis ◽  
Kalliopi Radoglou
Keyword(s):  
Root Biomass ◽  
Weight Ratio ◽  
Dry Weight ◽  
Total Phenolic ◽  
Root Weight ◽  
Light Emitting ◽  
Shoot Dry Weight ◽  
Radiation Spectra ◽  
Salvia Fruticosa ◽  
Developmental Characteristics

The effect of light-emitting diodes (LED) with broad radiation spectra on developmental, physiological, and phytochemical characteristics of Greek sage (Salvia fruticosa L.) seedlings was assessed. Fluorescent (FL – control) tubes and four LED lights [AP67 (moderate blue, red and far-red), L20AP67 (moderate blue, red and far-red, high green), AP673L (moderate blue, high red) and NS1 (high blue and green, low red, high red : far-red, 1% ultraviolet)] were used in a growth chamber. Seedlings grown under FL, L20AP67 and AP673L exhibited the best morphological and developmental characteristics. FL led to inferior root biomass formation compared to all LEDs. AP67 promoted greater root-to-shoot dry weight ratio and dry-to-fresh overground and root weight ratios, but induced the least morphological and developmental characteristics. NS1 performed well regarding the root biomass production. Total phenolic content and the root growth capacity were not significantly affected. The present study demonstrates that L20AP67 and AP673L LEDs performed equally to FL light regarding the developmental characteristics. AP67 and NS1 may have the potential to be used for compact seedling production.

scholarly journals Transmural distribution of metabolic abnormalities and glycolytic activity during dobutamine-induced demand ischemia

2008 ◽  
Vol 294 (6) ◽  
pp. H2680-H2686 ◽  
Author(s):  
Mohammad N. Jameel ◽  
Xiaohong Wang ◽  
Marcel H. J. Eijgelshoven ◽  
Abdul Mansoor ◽  
Jianyi Zhang
Keyword(s):  
Blood Flow ◽  
Coronary Stenosis ◽  
Energy Demand ◽  
Weight Ratio ◽  
Dry Weight ◽  
High Energy ◽  
Left Ventricular ◽  
Cardiac Work ◽  
Induced Demand ◽  
Systolic Thickening

The heterogeneity across the left ventricular wall is characterized by higher rates of oxygen consumption, systolic thickening fraction, myocardial perfusion, and lower energetic state in the subendocardial layers (ENDO). During dobutamine stimulation-induced demand ischemia, the transmural distribution of energy demand and metabolic markers of ischemia are not known. In this study, hemodynamics, transmural high-energy phosphate (HEP), 2-deoxyglucose-6-phosphate (2-DGP) levels, and myocardial blood flow (MBF) were determined under basal conditions, during dobutamine infusion (DOB: 20 μg·kg−1·min−1 iv), and during coronary stenosis + DOB + 2-deoxyglucose (2-DG) infusion. DOB increased rate pressure products (RPP) and MBF significantly without affecting the subendocardial-to-subepicardial blood flow ratio (ENDO/EPI) or HEP levels. During coronary stenosis + DOB + 2-DG infusion, RPP, ischemic zone (IZ) MBF, and ENDO/EPI decreased significantly. The IZ ratio of creatine phosphate-to-ATP decreased significantly [2.30 ± 0.14, 2.06 ± 0.13, and 2.04 ± 0.11 to 1.77 ± 0.12, 1.70 ± 0.11, and 1.72 ± 0.12 for EPI, midmyocardial (MID), and ENDO, respectively], and 2-DGP accumulated in all layers, as evidenced by the 2-DGP/PCr (0.55 ± 0.12, 0.52 ± 0.10, and 0.37 ± 0.08 for EPI, MID, and ENDO, respectively; P < 0.05, EPI > ENDO). In the IZ the wet weight-to-dry weight ratio was significantly increased compared with the normal zone (5.9 ± 0.5 vs. 4.4 ± 0.4; P < 0.05). Thus, in the stenotic perfused bed, during dobutamine-induced high cardiac work state, despite higher blood flow, the subepicardial layers showed the greater metabolic changes characterized by a shift toward higher carbohydrate metabolism, suggesting that a homeostatic response to high-cardiac work state is characterized by more glucose utilization in energy metabolism.

Infused salbutamol accentuates acid-induced lung injury in the rat

1986 ◽  
Vol 71 (2) ◽  
pp. 205-209 ◽  
Author(s):  
Stanley Braude ◽  
David Royston
Keyword(s):  
Lung Injury ◽  
Intravenous Infusion ◽  
Time Course ◽  
Weight Ratio ◽  
Dry Weight ◽  
Adrenergic Agonist ◽  
Lung Water ◽  
Significant Difference ◽  
And Control ◽  
Control Infusion

1. The effect in the rat of salbutamol infusion (1 μg min−1 kg−1) on acid-induced lung injury has been determined. Severity of lung injury was assessed by two techniques: the pulmonary clearance of 99mTc-diethylenetriaminepenta-acetate (99mTc-DTPA) and the lung wet/dry weight ratio, giving indices of alveolar epithelial permeability and transendothelial water filtration respectively. 2. Mean half-time of clearance of 99mTc-DTPA was increased significantly in rats who had intratracheal acid-induced injury and control (saline) intravenous infusion (19.4 ± 2.6 min) compared with non-acid-treated rats (98.1 ± 7.2) (P < 0.0001). However, those animals who had intratracheal acid injury and subsequent salbutamol intravenous infusion had significantly faster clearance (11.5 ± 1.9) than the acid and control infusion group (P < 0.05). 3. Gravimetric lung water in the acid-only rats (expressed as wet/dry weight ratio) was increased significantly (6.4 ± 0.3) compared with the non-acid-treated controls (5.4 ± 0.2) (P < 0.01). Acid-treated rats who had salbutamol infused had dramatically increased lung water (10.0 ± 0.6) (P < 0.001 vs acid and control infusion). 4. Intravenous salbutamol infusion itself produced no significant difference in the results for both techniques, compared with the non-acid-treated time-course controls. 5. Infused salbutamol accentuates acid-induced lung injury in the rat. Possible factors responsible for these findings include β2-adrenergic agonist mediated inhibition of hypoxic pulmonary vasoconstriction (HPV) and a predominant β1-adrenergic agonist inotropic effect of salbutamol with resultant rise in pulmonary artery pressure.

scholarly journals Management of Acute Lung Injury: Palmitoylethanolamide as a New Approach

2021 ◽  
Vol 22 (11) ◽  
pp. 5533
Author(s):  
Alessio Filippo Peritore ◽  
Ramona D’Amico ◽  
Rosalba Siracusa ◽  
Marika Cordaro ◽  
Roberta Fusco ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
B Cells ◽  
Lung Injury ◽  
Weight Ratio ◽  
Dry Weight ◽  
Mitogen Activated Protein Kinase ◽  
Histopathological Analysis ◽  
Nuclear Factor ◽  
Intratracheal Administration ◽  
Mitogen Activated Protein

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are common and devastating clinical disorders with high mortality and no specific therapy. Lipopolysaccharide (LPS) is usually used intratracheally to induce ALI in mice. The aim of this study was to examine the effects of an ultramicronized preparation of palmitoylethanolamide (um-PEA) in mice subjected to LPS-induced ALI. Histopathological analysis reveals that um-PEA reduced alteration in lung after LPS intratracheal administration. Besides, um-PEA decreased wet/dry weight ratio and myeloperoxidase, a marker of neutrophils infiltration, macrophages and total immune cells number and mast cells degranulation in lung. Moreover, um-PEA could also decrease cytokines release of interleukin (IL)-6, interleukin (IL)-1β, tumor necrosis factor (TNF)-α and interleukin (IL)-18. Furthermore, um-PEA significantly inhibited the phosphorylation of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation in ALI, and at the same time decreased extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38/MAPK) expression, that was increased after LPS administration. Our study suggested that um-PEA contrasted LPS-induced ALI, exerting its potential role as an adjuvant anti-inflammatory therapeutic for treating lung injury, maybe also by p38/NF-κB pathway.

The Relation of Oxygen Consumption to Body Size and to Temperature in the Larvae of Chironomus Riparius Meigen

1958 ◽  
Vol 35 (2) ◽  
pp. 383-395
Author(s):  
R. W. EDWARDS
Keyword(s):  
Oxygen Consumption ◽  
Body Size ◽  
Dry Matter ◽  
Larval Instar ◽  
Weight Ratio ◽  
Dry Weight ◽  
Chironomus Riparius ◽  
Consumption Rates ◽  
Rate Of Oxygen Consumption ◽  
Wet Weight

1. The oxygen consumption rates of 3rd- and 4th-instar larvae of Chironomus riparius have been measured at 10 and 20° C. using a constant-volume respirometer. 2. The oxygen consumption is approximately proportional to the 0.7 power of the dry weight: it is not proportional to the estimated surface area. 3. This relationship between oxygen consumption and dry weight is the same at 10 and at 20° C.. 4. The rate of oxygen consumption at 20° C. is greater than at 10° C. by a factor of 2.6. 5. During growth the percentage of dry matter of 4th-instar larvae increases from 10 to 16 and the specific gravity from 1.030 to 1.043. 6. The change in the dry weight/wet weight ratio during the 4 larval instar supports the theory of heterauxesis. 7. At 20° C., ‘summer’ larvae respire faster than ‘winter’ larvae.

Bathing Solution Tonicity and Potassium Transport by the Midgut of the Tobacco Hornworm Manduca Sexta

1979 ◽  
Vol 78 (1) ◽  
pp. 213-223
Author(s):  
DAVID F. MOFFETT
Keyword(s):  
Manduca Sexta ◽  
Short Circuit ◽  
Weight Ratio ◽  
Short Circuit Current ◽  
Dry Weight ◽  
Potassium Transport ◽  
Bathing Solution ◽  
Histological Studies ◽  
Wet Weight ◽  
Small Solute

Potassium transport by the isolated midgut of Manduca larvae, as measured by the short circuit current, is inhibited by substitution of small organic solutes (M.W. &lt; 340) for the sucrose normally included in bathing solution formulated for this tissue. Other solutes of molecular weight equal to or greater than sucrose are essentially as effective as sucrose in promoting the short circuit current. Equilibration of midgut in solutions containing the small solute mannitol results in a decrease in the dry weight/wet weight ratio of the tissue, suggesting that the small solutes can penetrate into areas of the tissue which are not accessible to sucrose. Histological studies suggest that sites of swelling in the presence of mannitol include both cytoplasm and goblet cell lumen. The inhibition of the short circuit current is rapidly reversible on return to bathing solution containing sucrose or another large solute. The effect of small solutes probably does not involve compromise of the energy source for potassium transport since oxygen uptake is unchanged in the presence of a small solute.

Immunotargeting of catalase to lung endothelium via anti-angiotensin-converting enzyme antibodies attenuates ischemia-reperfusion injury of the lung in vivo

2007 ◽  
Vol 293 (1) ◽  
pp. L162-L169 ◽  
Author(s):  
Kai Nowak ◽  
Sandra Weih ◽  
Roman Metzger ◽  
Ronald F. Albrecht ◽  
Stefan Post ◽  
...  
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Weight Ratio ◽  
Dry Weight ◽  
Serum Levels ◽  
Converting Enzyme ◽  
Pulmonary Endothelium ◽  
Preferential Expression

Limitation of reactive oxygen species-mediated ischemia-reperfusion (I/R) injury of the lung by vascular immunotargeting of antioxidative enzymes has the potential to become a promising modality for extension of the viability of banked transplantation tissue. The preferential expression of angiotensin-converting enzyme (ACE) in pulmonary capillaries makes it an ideal target for therapy directed toward the pulmonary endothelium. Conjugates of ACE monoclonal antibody (MAb) 9B9 with catalase (9B9-CAT) have been evaluated in vivo for limitation of lung I/R injury in rats. Ischemia of the right lung was induced for 60 min followed by 120 min of reperfusion. Sham-operated animals (sham, n = 6) were compared with ischemia-reperfused untreated animals (I/R, n = 6), I/R animals treated with biotinylated catalase (CAT, n = 6), and I/R rats treated with the conjugates (9B9-CAT, n = 6). The 9B9-CAT accumulation in the pulmonary endothelium of injured lungs was elucidated immunohistochemically. Arterial oxygenation during reperfusion was significantly higher in 9B9-CAT (221 ± 36 mmHg) and sham (215 ± 16 mmHg; P < 0.001 for both) compared with I/R (110 ± 10 mmHg) and CAT (114 ± 30 mmHg). Wet-dry weight ratio of I/R (6.78 ± 0.94%) and CAT (6.54 ± 0.87%) was significantly higher than of sham (4.85 ± 0.29%; P < 0.05), which did not differ from 9B9-CAT (5.58 ± 0.80%). The significantly lower degree of lung injury in 9B9-CAT-treated animals compared with I/R rats was also shown by decreased serum levels of endothelin-1 (sham, 18 ± 9 fmol/mg; I/R, 42 ± 12 fmol/mg; CAT, 36 ± 11 fmol/mg; 9B9-CAT, 26 ± 9 fmol/mg; P < 0.01) and mRNA for inducible nitric oxide synthase (iNOS) [iNOS-GAPDH ratio: sham, 0.15 ± 0.06 arbitrary units (a.u.); I/R, 0.33 ± 0.08 a.u.; CAT, 0.26 ± 0.05 a.u.; 9B9-CAT, 0.14 ± 0.04 a.u.; P < 0.001]. These results validate immunotargeting by anti-ACE conjugates as a prospective and specific strategy to augment antioxidative defenses of the pulmonary endothelium in vivo.

Experimental study on strength of cement stabilized clay

2005 ◽  
Vol 3 (2) ◽  
pp. 116-126 ◽  
Author(s):  
Woo‐Sik Kim ◽  
Nguyen Minh Tam ◽  
Du‐Hwoe Jung
Keyword(s):  
Compressive Strength ◽  
Soil Type ◽  
Unconfined Compressive Strength ◽  
Weight Ratio ◽  
Dry Weight ◽  
Strength Characteristics ◽  
Curing Time ◽  
Compression Tests ◽  
Soil Cement ◽  
Mixing Method

This paper describes the effect of factors on the strength characteristics of cement treated clay from laboratory tests performed on cement mixed clay specimens. It is considered that several factors such as soil type, sample preparing method, quantity of binder, curing time, etc. can have an effect on strength characteristics of cement stabilized clay. A series of unconfined compression tests have been performed on samples prepared with different conditions. The results indicated that soil type, mixing method, curing time, dry weight ratio of cement to clay (Aw), and water‐clay to cement (wc/c) ratio were main factors which can have an influence on unconfined compressive strength, modulus of elasticity, and failure strain of cement stabilized clay. Unconfined compressive strength of soil‐cement samples prepared from dry mixing method was higher than those prepared from wet mixing method.

Effect of pulmonary artery occlusion and reperfusion on extravascular fluid accumulation

1981 ◽  
Vol 50 (1) ◽  
pp. 102-106 ◽  
Author(s):  
P. S. Barie ◽  
T. S. Hakim ◽  
A. B. Malik
Keyword(s):  
Pulmonary Artery ◽  
Water Content ◽  
Left Atrial ◽  
Left Lung ◽  
Weight Ratio ◽  
Dry Weight ◽  
Left Pulmonary Artery ◽  
Artery Occlusion ◽  
Lung Water ◽  
The Right

We determined the effect of pulmonary hypoperfusion on extravascular water accumulation in anesthetized dogs by occluding the left pulmonary artery for 3 h and then reperfusing it for 24 h. The lung was reperfused either at normal left atrial pressure (Pla) or during increased Pla induced by a left atrial balloon. In each case the extravascular water content-to-bloodless dry weight ratio (W/D) of the left lung was compared with that of the right lung. The W/D of the left lung of 3.26 +/- 0.49 ml/g was not significantly different from the value of 2.87 +/- 0.37 for the right lung after the reperfusion at normal Pla. However, the W/D of the left lung of 5.10 +/- 0.38 ml/g was greater (P less than 0.05) than the value of 4.42 +/- 0.34 for the right lung after reperfusion at Pla of 25 Torr. This difference could not be prevented by pretreatment with heparin, suggesting that the increase in lung water content was not due to activation of intravascular coagulation secondary to stasis occurring during the occlusion. Because the left lung was more edematous than the right one, even though both lungs had been subjected to the same increase in Pla, the results suggest that a period of pulmonary hypoperfusion causes an increase in the interstitial protein concentration.

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