The Effects of Oxygen Supply, Epinephrine, and Acetylcholine on the Distribution of Blood Flow in Trout Gills

1979 ◽  
Vol 83 (1) ◽  
pp. 31-39 ◽  
Author(s):  
JOHN H. BOOTH
Keyword(s):  
Blood Flow ◽  
Liquid Nitrogen ◽  
Blood Cells ◽  
Adrenergic Receptors ◽  
Oxygen Supply ◽  
Central Compartment ◽  
Rapid Freezing ◽  
Saturated Water ◽  
Secondary Lamellae ◽  
Ventral Aorta

Injecting vitally stained blood cells into the ventral aorta of unrestrained, cannulated fish, and rapid freezing in liquid nitrogen, permitted the examination of the effects of oxygen supply, epinephrine and acetylcholine on branchial lamellar perfusion. Compared to the conditions in resting fish in air-saturated water, hypoxia and injection of epinephrine significantly increased the proportion of secondary lamellae receiving stained cells, and acetylcholine caused a significant reduction, but hyperoxia did not significantly affect the proportion of lamellae containing stained cells. Perfusion of the filamental central compartment was not affected by the treatments. It is concluded that trout can respond to changes in oxygen supply by varying the number of secondary lamellae perfused with blood, and that the distribution of blood flow is regulated by cholinergic and adrenergic receptors. It is suggested, however, that lamellar recruitment would not be useful in minimizing the costs of osmo- and iono-regulation.

scholarly journals The Distribution of Blood Flow in the Gills of Fish: Application of a New Technique to Rainbow Trout (Salmo Gairdneri)

1978 ◽  
Vol 73 (1) ◽  
pp. 119-129 ◽  
Author(s):  
JOHN H. BOOTH
Keyword(s):  
Blood Flow ◽  
Rainbow Trout ◽  
Central Compartment ◽  
Salmo Gairdneri ◽  
Functional Surface ◽  
Saturated Water ◽  
Secondary Lamellae ◽  
Ventral Aorta ◽  
A New Technique ◽  
Blood Flow Patterns

Injecting vitally stained blood cells into the ventral aorta of unrestrained cannulated fish, and rapid freezing in liquid nitrogen, provided a method of investigating blood flow patterns in the gills. Rainbow trout in air-saturated water perfused an average of 58% of the secondary lamellae of the gills. Perfusion of the filamental central compartment was insignificant indicating that the effects of any non-respiratory shunting would be unimportant. If the functional surface area of the gills is variable, it seems likely that this would be accomplished through lamellar recruitment. There was no evidence that pillar cell contraction affected lamellar perfusion. There was preferential perfusion of lamellae near the base of the filaments, and of filaments near the dorsal end of the gill arches.

Transport: blood and circulation

2017 ◽  
Author(s):  
Derek Burton ◽  
Margaret Burton
Keyword(s):  
Carbon Dioxide ◽  
Blood Cells ◽  
Venous Return ◽  
White Blood Cells ◽  
Nutrient Transport ◽  
Blood System ◽  
Fluid Component ◽  
Nucleated Red Blood Cells ◽  
Ventral Aorta ◽  
Osmotic Effects

The blood system transports nutrients, oxygen, carbon dioxide and nitrogenous wastes; other functions include defence. Fish have a closed, single circulation in which blood is pumped by a contractile heart via a ventral aorta to the gills, then via the dorsal aorta to vessels supplying the tissues and organs, with a venous return to the heart. Large venous sinuses occur in elasmobranchs. Air-breathing fish have modifications of the circulation. Complex networks of narrow blood vessels can occur as red patches, retia, maximizing transfer of nutrients, oxygen or heat. Most fish have nucleated red blood cells (erythrocytes) with haemoglobin. The types of white blood cells (leucocytes) are similar to those of other vertebrates but there are thrombocytes rather than platelets. Nutrient transport is in the plasma, the fluid component of the blood, which may also carry antifreeze agents and molecules (e.g. urea in elasmobranchs) which counteract deleterious osmotic effects

scholarly journals Mathematical Models for Some Aspects of Blood Microcirculation

Symmetry ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1020
Author(s):  
Angiolo Farina ◽  
Antonio Fasano ◽  
Fabio Rosso
Keyword(s):  
Blood Flow ◽  
Mathematical Models ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Blood Rheology ◽  
Small Class ◽  
Small Vessels ◽  
Blood Microcirculation ◽  
Peculiar Behavior

Blood rheology is a challenging subject owing to the fact that blood is a mixture of a fluid (plasma) and of cells, among which red blood cells make about 50% of the total volume. It is precisely this circumstance that originates the peculiar behavior of blood flow in small vessels (i.e., roughly speaking, vessel with a diameter less than half a millimeter). In this class we find arteriolas, venules, and capillaries. The phenomena taking place in microcirculation are very important in supporting life. Everybody knows the importance of blood filtration in kidneys, but other phenomena, of not less importance, are known only to a small class of physicians. Overviewing such subjects reveals the fascinating complexity of microcirculation.

Multiscale Modeling of Flow Induced Thrombogenicity Using Dissipative Particle Dynamics and Molecular Dynamics

2013 ◽  
Author(s):  
Danny Bluestein ◽  
João S. Soares ◽  
Peng Zhang ◽  
Chao Gao ◽  
Seetha Pothapragada ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Blood Flow ◽  
Red Blood Cells ◽  
Platelet Activation ◽  
Blood Cells ◽  
Dissipative Particle Dynamics ◽  
Particle Dynamics ◽  
Coagulation Cascade ◽  
Shear Stresses ◽  
Activated Platelets

The coagulation cascade of blood may be initiated by flow induced platelet activation, which prompts clot formation in prosthetic cardiovascular devices and arterial disease processes. While platelet activation may be induced by biochemical agonists, shear stresses arising from pathological flow patterns enhance the propensity of platelets to activate and initiate the intrinsic pathway of coagulation, leading to thrombosis. Upon activation platelets undergo complex biochemical and morphological changes: organelles are centralized, membrane glycoproteins undergo conformational changes, and adhesive pseudopods are extended. Activated platelets polymerize fibrinogen into a fibrin network that enmeshes red blood cells. Activated platelets also cross-talk and aggregate to form thrombi. Current numerical simulations to model this complex process mostly treat blood as a continuum and solve the Navier-Stokes equations governing blood flow, coupled with diffusion-convection-reaction equations. It requires various complex constitutive relations or simplifying assumptions, and is limited to μm level scales. However, molecular mechanisms governing platelet shape change upon activation and their effect on rheological properties can be in the nm level scales. To address this challenge, a multiscale approach which departs from continuum approaches, may offer an effective means to bridge the gap between macroscopic flow and cellular scales. Molecular dynamics (MD) and dissipative particle dynamics (DPD) methods have been employed in recent years to simulate complex processes at the molecular scales, and various viscous fluids at low-to-high Reynolds numbers at mesoscopic scales. Such particle methods possess important properties at the mesoscopic scale: complex fluids with heterogeneous particles can be modeled, allowing the simulation of processes which are otherwise very difficult to solve by continuum approaches. It is becoming a powerful tool for simulating complex blood flow, red blood cells interactions, and platelet-mediated thrombosis involving platelet activation, aggregation, and adhesion.

Right and left ventricular O2 uptake during hemodilution and beta-adrenergic stimulation

1993 ◽  
Vol 265 (5) ◽  
pp. H1769-H1777 ◽  
Author(s):  
G. J. Crystal ◽  
S. J. Kim ◽  
M. R. Salem
Keyword(s):  
Blood Flow ◽  
Blood Cells ◽  
Left Ventricular ◽  
Adrenergic Stimulation ◽  
O2 Uptake ◽  
Isovolemic Hemodilution ◽  
Content Difference ◽  
O2 Extraction ◽  
In Series ◽  
O2 Delivery

Myocardial O2 uptake (MVO2) and related variables were compared in right and left ventricles (RV and LV, respectively) during isovolemic hemodilution (HD) alone and combined with isoproterenol (Iso) infusion in 13 isoflurane-anesthetized open-chest dogs. Measurements of myocardial blood flow (MBF) obtained with radioactive microspheres were used to calculate MVO2. Lactate extraction (Lacext) was determined. The study consisted of two experimental series: 1) graded HD (dextran) to hematocrit (Hct) of 10% and 2) Iso (0.1 microgram.kg-1.min-1 iv) during moderate HD (Hct = 18 +/- 1%). In series 1, arteriovenous O2 content difference in both ventricles decreased in parallel with reduced arterial O2 content caused by HD, i.e., percent O2 extraction was constant; MVO2 was maintained by proportional increases in MBF. In series 2, Iso during moderate HD raised MVO2 (RV, +156%; LV, +80%). Higher MVO2 was satisfied by combination of increased MBF and O2 extraction in RV and by increased MBF alone in LV. Lacext remained consistent with adequate myocardial O2 delivery throughout study. Conclusions were that 1) both RV and LV tolerated extreme HD (Hct = 10%) because blood flow reserves were sufficient to fully compensate for reduced arterial O2 content; 2) significant cardiac reserve was evident during HD, which could be recruited Iso; and 3) because increase in MVO2 in RV caused by Iso in presence of HD was partially satisfied by increased O2 extraction, the absence of augmented O2 extraction during HD alone was not due to impaired release of O2 from diluted red blood cells.(ABSTRACT TRUNCATED AT 250 WORDS)

MODELLING HYDROGEN CLEARANCE FROM THE RETINA

2018 ◽  
Vol 59 (3) ◽  
pp. 281-292
Author(s):  
D. E. FARROW ◽  
G. C. HOCKING ◽  
S. J. CRINGLE ◽  
D.-Y. YU
Keyword(s):  
Blood Flow ◽  
Oxygen Supply ◽  
Retinal Blood Flow ◽  
Experimental Measurements ◽  
Human Retina ◽  
Light Path ◽  
Tissue Oxygen ◽  
Sophisticated Model ◽  
Tissue Oxygen Supply ◽  
Hydrogen Clearance

The human retina is supplied by two vascular systems: the highly vascular choroidal, situated behind the retina; and the retinal, which is dependent on the restriction that the light path must be minimally disrupted. Between these two circulations, the avascular retinal layers depend on diffusion of metabolites through the tissue. Oxygen supply to these layers may be threatened by diseases affecting microvasculature, for example diabetes and hypertension, which may ultimately cause loss of sight.An accurate model of retinal blood flow will therefore facilitate the study of retinal oxygen supply and, hence, the complications caused by systemic vascular disease. Here, two simple models of the blood flow and exchange of hydrogen with the retina are presented and compared qualitatively with data obtained from experimental measurements. The models capture some interesting features of the exchange and highlight effects that will need to be considered in a more sophisticated model and in the interpretation of experimental results.

Whole body autoradiography and microautoradiography in eels after intra-arterial administration of 125I-labeled eel ANP

1996 ◽  
Vol 271 (4) ◽  
pp. R926-R935 ◽  
Author(s):  
H. Sakaguchi ◽  
H. Suzuki ◽  
H. Hagiwara ◽  
H. Kaiya ◽  
Y. Takei ◽  
...  
Keyword(s):  
Binding Sites ◽  
Head Kidney ◽  
Dorsal Aorta ◽  
Whole Body ◽  
Whole Body Autoradiography ◽  
Target Organs ◽  
Secondary Lamellae ◽  
Ventral Aorta ◽  
Interrenal Cells ◽  
Kidney Liver

125I-labeled eel atrial natriuretic peptide (ANP) was administered into the ventral or dorsal aorta of freshwater (FW) and seawater (SW) eels, Anguilla japonica, and the major target organs were explored by whole body autoradiography. Localization of the ANP binding in the target organs was also examined at tissue and cell levels by microautoradiography using tissue sections. Whole body autoradiography revealed that the specific label was accumulated predominantly in the gill, with lesser amounts in the atrium, kidney, liver, and urinary bladder. Autoradiographic grains were most dense in the secondary lamellae of the gill, particularly on the side of the efferent filamental artery. Other binding sites in target tissues were the glomerulus of the kidney, epicardium and endocardium of the atrium, bile duct/blood vessels of the liver, and interrenal cells of the head kidney. There was no difference in the distribution and density of grains between injections into the ventral aorta and dorsal aorta, although, in the former, injected 125I-labeled eel ANP passes through the gill before reaching peripheral target tissues. There was a tendency for downregulation of ANP binding sites in SW eels, especially in the gill. These results show that specific ANP binding sites are present in organs that are implicated in osmoregulation and cardiovascular regulation in eels and further suggest that the number of ANP binding sites varies according to changes in the environmental salinity.

scholarly journals PROSPECTS FOR TREATMENT AND LIFE-SAVING FOR PATIENTS WITH CORONAVIRUS INFECTION

2020 ◽  
Vol 5 (7(76)) ◽  
pp. 44-51
Author(s):  
Alexander Alexeyevich Medenkov ◽  
Vitaly Nikolayevich Frantsuzov ◽  
Mikhail Vyacheslavovich Dvornikov
Keyword(s):  
Gas Exchange ◽  
Medical Practice ◽  
Blood Cells ◽  
Oxygen Supply ◽  
Blood Substitute ◽  
Symptomatic Treatment ◽  
Analysis Of Means ◽  
Life Saving ◽  
History Of ◽  
Coronavirus Infection

The article is devoted to the analysis of means of symptomatic treatment of coronavirus infection. Pathogenesis and symptoms of damage to organs and systems are considered. The main mechanisms of disruption of blood supply to organs and tissues are noted. The history of the development and use of perfluorane in disorders of gas exchange in the lungs and the function of red blood cells to transport oxygen is presented. Data on the effectiveness of the use of blood substitute in medical practice is considered. The properties and qualities of perfluorane and the mechanisms of its action to improve the oxygen supply of organs and tissues are considered. Evidence of the use of perfluorane in various diseases is given. The prospect of using perfluorane for the treatment of patients with coronavirus infection has been shown.

Sign in / Sign up

Export Citation Format

Share Document