scholarly journals Blood Perfusion of the Kidney of Lophius Piscatorius L.

1953 ◽  
Vol 32 (2) ◽  
pp. 329-336 ◽  
Author(s):  
L. Brull ◽  
E. Nizet ◽  
E. B. Verney
Keyword(s):  
Blood Flow ◽  
Critical Level ◽  
Perfusion Pressure ◽  
Blood Perfusion ◽  
Urine Flow ◽  
The Other ◽  
Protein Nitrogen ◽  
Other Hand ◽  
Flow Through

Lophius kidneys perfused with the heparinized blood (venous) of the fish secrete urine in which total non-protein nitrogen is concentrated, magnesium highly concentrated, and chloride only slightly so or not at all. Oxygenation of the blood, or lowering the temperature of the perfusate from c. 20° to c. 5° C. does not appear to influence secretion. The blood flow through the kidneys increases with the perfusion pressure, the increase often becoming disproportionately large. The urine flow, on the other hand, above a certain critical level is largely independent of changes in perfusion pressure.

scholarly journals Blood perfusion of the kidney of Lophius piscatorius L.: II. Influence of perfusion pressure on urine volume

1954 ◽  
Vol 33 (3) ◽  
pp. 733-738 ◽  
Author(s):  
L. Brull ◽  
Y. Cuypers
Keyword(s):  
Blood Flow ◽  
Oxygen Consumption ◽  
Critical Level ◽  
Perfusion Pressure ◽  
Urine Volume ◽  
Blood Perfusion ◽  
Urine Flow ◽  
Active Process ◽  
Flow Through ◽  
Water Secretion

SummaryThe urine secretion of the kidneys of Lophius piscatorius perfused with heparinized Lophius blood is very sensitive to perfusion pressure below a critical level, above which it becomes insensitive. The response of the urine flow to pressure takes the form of an exponential curve.The blood flow through the kidneys, while rising slowly at pressures of about 20–30 mm of water, responds arithmetically to pressure above such levels.At present it is impossible to make out whether pressure or blood flow has the greatest influence on secretion.Water secretion in the aglomerular kidney is an active process. The oxygen consumption of the Lophius kidney is unmeasurably low, yet remains a possible factor in secretion.

Effect of injections of hypertonic solutions on blood flow through the femoral artery of the dog

1959 ◽  
Vol 197 (5) ◽  
pp. 951-954 ◽  
Author(s):  
Robert J. Marshall ◽  
John T. Shepherd
Keyword(s):  
Blood Flow ◽  
Femoral Artery ◽  
Perfusion Pressure ◽  
The Other ◽  
Nacl Solution ◽  
Small Vessels ◽  
Threefold Increase ◽  
Hypertonic Solutions ◽  
Initial Reduction ◽  
Flow Through

Blood flow through the femoral artery was measured in 10 dogs; a bubble flowmeter was used in 5 and, in the other 5, an ultrasonic flowmeter was used. Rapid injections of 2 ml of 10–20% solution of NaCl caused a definite but transient reduction in flow, followed by a prolonged twofold to threefold increase. Similar effects were noted with other Na salts and also with 25–50% dextrose solution. The use of 25 and 50% solutions of urea caused only a prolonged increase in flow. Isotonic NaCl solution had little or no effect. Continuous infusions at 2.3 ml/min. of 10 and 20% solution of NaCl and 50% dextrose and urea solutions caused only doubled to tripled increase in flow which continued throughout infusion. The initial reduction in flow cannot be explained by reduction in perfusion pressure and may result from reversible hemagglutination in small vessels. The increase in flow is due to vasodilatation locally mediated, since it could not be accounted for by changes in perfusion pressure and was unchanged after denervation of the leg. The mechanism of the dilatation is uncertain, but since it occurs with salt-free hypertonic solutions it is not specific for sodium-containing salts.

Blood flow elevation increases VO2 maximum during repetitive tetanic contractions of dog muscle in situ

1993 ◽  
Vol 74 (4) ◽  
pp. 1499-1503 ◽  
Author(s):  
W. F. Brechue ◽  
B. T. Ameredes ◽  
G. M. Andrew ◽  
W. N. Stainsby
Keyword(s):  
Blood Flow ◽  
Perfusion Pressure ◽  
Power Production ◽  
Arterial Supply ◽  
O2 Uptake ◽  
Plantaris Muscle ◽  
Control Series ◽  
Flow Through ◽  
Series Of Experiments

Blood flow through the gastrocnemius-plantaris muscle of the dog in situ was increased by a pump in the arterial supply during a 30-min period of 1/s isotonic tetanic contractions. Compared with a control series of experiments with normoxemia and spontaneous flow, the pump increased flow 84%, from 1.51 +/- 0.08 to 2.78 +/- 0.15 ml.g-1.min-1. The perfusion pressure was increased from 125 to 196 mmHg. The pump hyperemia increased maximal O2 uptake (VO2) at 5 min of contractions by 31%, from 8.97 +/- 0.44 to 12.89 +/- 0.30 mumol.g-1.min-1. The extraction was decreased, and venous PO2 (PVO2) was increased. Fatigue, measured as a drop in power production from the highest level at 10 s to 30 min, was 49% during pump hyperemia and 54% in the control conditions. VO2 decreased 30% from the 5-min value to the 30-min value with pump hyperemia and 28% over the same time in the control conditions. At maximal VO2, the ratio VO2/PVO2 was increased by pump hyperemia compared with control conditions, suggesting an increased O2 diffusing conductance of the muscles. We conclude that the elevated perfusion pressure of pump hyperemia increased flow to raise maximal VO2 mainly in areas of the muscle that had restricted flow under control conditions.

scholarly journals Cerebral Blood Flow in Patients with Intracranial Pressure Elevation due to Traumatic Brain Edema

1976 ◽  
Vol 3 (1) ◽  
pp. 35-37 ◽  
Author(s):  
W. A. Tweed ◽  
Jørn Overgaard
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Intracranial Pressure ◽  
Brain Edema ◽  
Cerebral Perfusion ◽  
Perfusion Pressure ◽  
Monitoring And Control ◽  
Intracranial Pressure Elevation ◽  
Flow Through ◽  
And Control

SUMMARY:The object of this study was to determine if traumatic brain edema (BE) and increased intracranial pressure (ICP) reduce cerebral blood flow (CBF). Two groups of patients were studied, one with slight BE and ICP less than 20 mm Hg., the other with pronounced BE and ICP over 20 mm Hg. Although ICP was higher and cerebral perfusion pressure lower in pro-nounced edema there was only a small and non-significant reduction in CBF and no difference in cerebro-vascular resistance. Since traumatic BE does not increase resistance to blood flow through the brain, cerebral perfusion can be maintained if an adequate perfusion pressure is established. This in turn, demands the monitoring and control of ICP.

scholarly journals Cell Death–associated ADAMTS4 and Versican Degradation in Vascular Tissue

2009 ◽  
Vol 57 (9) ◽  
pp. 889-897 ◽  
Author(s):  
Richard D. Kenagy ◽  
Seung-Kee Min ◽  
Alexander W. Clowes ◽  
John D. Sandy
Keyword(s):  
Blood Flow ◽  
Cell Death ◽  
Smooth Muscle ◽  
Smooth Muscle Cell ◽  
Fas Ligand ◽  
Vascular Tissue ◽  
Transcript Abundance ◽  
High Flow ◽  
The Other ◽  
Flow Through

High blood flow through baboon polytetrafluorethylene aorto-iliac grafts increases neointimal vascular smooth muscle cell (SMC) death, neointimal atrophy, and cleavage of versican to generate the DPEAAE neoepitope, a marker of ADAMTS-mediated proteolysis. In this study, we have determined the effect of high blood flow on transcript abundance in the neointima for ADAMTS1, −4, −5, −8, −9, −15, and −20. We found that after 24 hr of flow, the mRNA for ADAMTS4 was significantly increased, whereas that for the other family members was unchanged. Because vascular SMC death is markedly increased in the graft after 24 hr of high flow, we next examined the possibility that the ADAMTS4 induction and the cell death are causally related. The addition of Fas ligand to SMC cultures increased both ADAMTS4 mRNA and cell death ∼5-fold, consistent with the idea that ADAMTS4-dependent cleavage of versican may be partly responsible for cell death and tissue atrophy under these conditions.

Noninvasive Blood Perfusion Measurement on the Liver of an Anesthetized Rat

2007 ◽  
Author(s):  
Patricia L. Ricketts ◽  
Ashvinikumar V. Mudaliar ◽  
Brent E. Ellis ◽  
Thomas E. Diller ◽  
Elaine P. Scott ◽  
...  
Keyword(s):  
Blood Flow ◽  
Environmental Factors ◽  
Large Range ◽  
Volumetric Flow Rate ◽  
Blood Perfusion ◽  
Tissue Type ◽  
Living Tissue ◽  
Measurement Sensitivity ◽  
Perfusion Measurement ◽  
Flow Through

Blood perfusion is the local, non-directional blood flow through living tissue. It is measured as the volumetric flow rate of blood per volume of tissue and a large range of perfusion values have been reported for human tissue (i.e. 0.002–0.5 ml/ml/s). This large range is thought to be due to measurement sensitivity, environmental factors, and tissue type and location.

Leukotriene inhibitors do not block hypoxic pulmonary vasoconstriction in dogs

1987 ◽  
Vol 62 (5) ◽  
pp. 1808-1813 ◽  
Author(s):  
D. P. Schuster ◽  
D. R. Dennis
Keyword(s):  
Blood Flow ◽  
Pulmonary Blood Flow ◽  
Pressor Response ◽  
Hypoxic Pulmonary Vasoconstriction ◽  
Lower Lobe ◽  
Left Lower Lobe ◽  
The Other ◽  
Pulmonary Vasoconstriction ◽  
Other Hand ◽  
Alveolar Hypoxia

We studied whether intravenously administered inhibitors of leukotriene synthesis (diethylcarbamazine, DEC) or end-organ effect (FPL-55712) would change the distribution of regional pulmonary blood flow (rPBF) caused by left lower lobe (LLL) alveolar hypoxia in dogs. Both drugs failed to alter rPBF. In addition, the pressor response to whole-lung hypoxia was not blocked by an FPL-55712 infusion. On the other hand, nitroprusside, as a nonspecific vasodilator also administered intravenously, was able to partially reverse the effects of LLL hypoxia on rPBF. Thus our data do not support a role for leukotriene mediation of hypoxic pulmonary vasoconstriction in dogs.

scholarly journals Blood perfusion of the kidney of Lophius piscatorius L.

1955 ◽  
Vol 34 (2) ◽  
pp. 217-222 ◽  
Author(s):  
L. Brull ◽  
Y. Cuypers ◽  
L. Wilsens
Keyword(s):  
Blood Flow ◽  
Blood Perfusion ◽  
Urine Flow ◽  
High Tension ◽  
Aerobic Processes ◽  
Water Secretion

SUMMARYKidneys of Lophius piscatorius L., perfused with heparinized blood, respond to a high tension of CO2 in the blood by a drop in urine flow and in their capacity for concentrating Mg. At the same time, but independently, CO2 reduces the blood flow. Both cyanide and fluoride may stop or reduce water secretion and Mg concentration, according to the concentration used, showing that both these activities are dependent on aerobic processes and presumably on the integrity of the carbohydrate cycle.

Measurement of Regional Sodium Turnover Rates and Their Application to the Estimation of Regional Blood Flow

1957 ◽  
Vol 189 (2) ◽  
pp. 269-276 ◽  
Author(s):  
Ernest L. Dobson ◽  
George F. Warner
Keyword(s):  
Blood Flow ◽  
Turnover Rate ◽  
Regional Blood Flow ◽  
Removal Rate ◽  
Subcutaneous Administration ◽  
Blood Perfusion ◽  
Turnover Rates ◽  
Epinephrine Administration ◽  
Vascular Bed ◽  
Flow Through

It has been possible to estimate the regional blood flow through quantitative analysis of the sodium wash out curve obtained by a method which involves the injection of sodium 24 into an artery and the subsequent monitoring of the region (limb) supplied by this artery with external counters. The normal resting sodium turnover rate in the human forearm was found to be 10%/min. corresponding to a blood perfusion factor of 0.040 liters of blood per liter of tissue per minute. In addition to these quantitative values this method has given qualitative information on the pattern of the vascular bed. Analysis of the manner in which the removal rate changes with time has indicated that there are regions of widely differing vascularities in the area seen by the counter. Measurements following epinephrine administration have demonstrated not only a quantitative change in flow but a qualitative one as well. The subcutaneous administration of 1 mg epinephrine caused a doubling of the average total sodium turnover rate indicating a twofold increase in blood flow. The observed changes in the shape of the clearance curves could not be explained by a simple increase in linear flow rate and therefore must have involved some change in the character of the vascular bed, i.e. the conversion of some regions of low vascularity to regions of high vascularity.

scholarly journals Exercise causes a tissue-specific change of NO production in the kidney and lung

2003 ◽  
Vol 94 (1) ◽  
pp. 60-68 ◽  
Author(s):  
Takashi Miyauchi ◽  
Seiji Maeda ◽  
Motoyuki Iemitsu ◽  
Tsutomu Kobayashi ◽  
Yoshito Kumagai ◽  
...  
Keyword(s):  
Blood Flow ◽  
The Other ◽  
Tissue Blood Flow ◽  
Inos Mrna ◽  
No Production ◽  
Tissue Specific ◽  
Specific Change ◽  
Other Hand ◽  
Nitrite Nitrate ◽  
And Control

Nitric oxide (NO) is produced in the vascular endothelium and is a potent vasodilator substance that participates in the regulation of local vascular tone. Exercise causes peculiar changes in systemic and regional blood flow, i.e., an increase of systemic blood flow and a redistribution of local tissue blood flow, by which the blood flow is greatly increased in the working muscles, whereas it is decreased in some organs such as the kidney and intestine. Thus we hypothesized that exercise causes a tissue-specific change of NO production in some internal organs. We studied whether exercise affects expression of NO synthase (NOS) mRNA and protein, NOS activity, and tissue level of nitrite/nitrate (stable end products of NO) in the kidneys (in which blood flow during exercise is decreased) and lungs (in which blood flow during exercise is increased with the increase of cardiac output) of rat. Rats ran on a treadmill for 45 min at a speed of 25 m/min. Immediately after this exercise, kidneys and lungs were quickly removed. Control rats remained at rest during this 45-min period. Expression of endothelial NOS (eNOS) mRNA in the kidneys was markedly lower in exercise rats than in control rats, whereas that in the lungs was significantly higher in exercise rats than in control rats. Western blot analysis confirmed down- and upregulation of eNOS protein in the kidney and lung, respectively, after exercise. On the other hand, neither expression of neuronal NOS (nNOS) mRNA and nNOS protein nor inducible NOS (iNOS) mRNA and iNOS protein in the kidneys and lungs differed between exercise and control rats. NOS activity in the kidney was significantly lower in exercise rats than in control rats, whereas that in the lung was significantly higher in exercise rats than in control rats. On the other hand, the iNOS activity in the kidneys and lungs did not differ between exercise rats and control rats. Tissue nitrite/nitrate level in the kidneys was markedly lower in exercise rats, whereas that in the lungs was significantly higher in exercise rats. The present results show that production of NO is markedly and tissue-specifically changed in the kidney and lung by exercise.

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