Biomaterial Database

Effect of volume expansion on papillary blood flow and sodium excretion. 1991

F J Fenoy, and R J Roman

Department of Physiology, Medical College of Wisconsin, Milwaukee 53226.

The present study examined whether changes in plasma oncotic pressure or hematocrit play a role in the redistribution of renal blood flow and the natriuretic response to extracellular fluid volume (ECFV) expansion with saline. Intravenous infusion of saline produced a 46% increase in the flow of red blood cells (RBCs) in the papilla of Inactin-anesthetized euvolemic Munich-Wistar rats (n = 6). This was primarily due to an increase in the number of functional capillaries perfused with moving RBCs, as indicated both by laser-Doppler flowmetry and videomicroscopy. The velocity of RBCs in ascending or descending vasa recta was not significantly altered by the infusion of saline. Plasma volume expansion with a 6% solution of albumin (n = 6) did not increase papillary RBC flow, whereas volume expansion with whole blood produced a 17% increase in the flow of RBCs in the papilla. Sodium excretion after ECFV expansion with saline (n = 6) was greater than that seen after plasma volume expansion with a 6% solution of albumin (n = 5). The results indicate that the rise in papillary RBC flow after ECFV expansion with saline is due to an increase in the number of perfused vasa recta capillaries. The failure of plasma volume expansion to alter papillary RBC flow suggests that changes in plasma oncotic pressure and/or renal interstitial pressure may signal the rise in papillary RBC flow after intravenous infusion of saline. The present study also indicates that laser-Doppler flowmetry is a useful technique to monitor changes in the flow, velocity, and concentration of moving RBCs in tissue.

UI	MeSH Term	Description	Entries
D007262	Infusions, Intravenous	The long-term (minutes to hours) administration of a fluid into the vein through venipuncture, either by letting the fluid flow by gravity or by pumping it.	Drip Infusions,Intravenous Drip,Intravenous Infusions,Drip Infusion,Drip, Intravenous,Infusion, Drip,Infusion, Intravenous,Infusions, Drip,Intravenous Infusion
D007679	Kidney Medulla	The internal portion of the kidney, consisting of striated conical masses, the renal pyramids, whose bases are adjacent to the cortex and whose apices form prominent papillae projecting into the lumen of the minor calyces.	Kidney Papilla,Kidney Medullas,Kidney Papillas,Medulla, Kidney,Medullas, Kidney,Papilla, Kidney,Papillas, Kidney
D008657	Metabolic Clearance Rate	Volume of biological fluid completely cleared of drug metabolites as measured in unit time. Elimination occurs as a result of metabolic processes in the kidney, liver, saliva, sweat, intestine, heart, brain, or other site.	Total Body Clearance Rate,Clearance Rate, Metabolic,Clearance Rates, Metabolic,Metabolic Clearance Rates,Rate, Metabolic Clearance,Rates, Metabolic Clearance
D008853	Microscopy	The use of instrumentation and techniques for visualizing material and details that cannot be seen by the unaided eye. It is usually done by enlarging images, transmitted by light or electron beams, with optical or magnetic lenses that magnify the entire image field. With scanning microscopy, images are generated by collecting output from the specimen in a point-by-point fashion, on a magnified scale, as it is scanned by a narrow beam of light or electrons, a laser, a conductive probe, or a topographical probe.	Compound Microscopy,Hand-Held Microscopy,Light Microscopy,Optical Microscopy,Simple Microscopy,Hand Held Microscopy,Microscopy, Compound,Microscopy, Hand-Held,Microscopy, Light,Microscopy, Optical,Microscopy, Simple
D010953	Plasma Volume	Volume of PLASMA in the circulation. It is usually measured by INDICATOR DILUTION TECHNIQUES.	Blood Plasma Volume,Blood Plasma Volumes,Plasma Volumes,Volume, Blood Plasma,Volume, Plasma,Volumes, Blood Plasma,Volumes, Plasma
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D012039	Regional Blood Flow	The flow of BLOOD through or around an organ or region of the body.	Blood Flow, Regional,Blood Flows, Regional,Flow, Regional Blood,Flows, Regional Blood,Regional Blood Flows
D006400	Hematocrit	The volume of packed RED BLOOD CELLS in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, ANEMIA shows a low value; POLYCYTHEMIA, a high value.	Erythrocyte Volume, Packed,Packed Red-Cell Volume,Erythrocyte Volumes, Packed,Hematocrits,Packed Erythrocyte Volume,Packed Erythrocyte Volumes,Packed Red Cell Volume,Packed Red-Cell Volumes,Red-Cell Volume, Packed,Red-Cell Volumes, Packed,Volume, Packed Erythrocyte,Volume, Packed Red-Cell,Volumes, Packed Erythrocyte,Volumes, Packed Red-Cell
D006439	Hemodynamics	The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.	Hemodynamic
D000418	Albumins	Water-soluble proteins found in egg whites, blood, lymph, and other tissues and fluids. They coagulate upon heating.	Albumin