Biomaterial Database

The effects of flow on the transport of potassium ions through the walls of single perfused frog mesenteric capillaries. 1998

M Kajimura, and S D Head, and C C Michel

Section of Cellular & Integrative Biology, Division of Biomedical Sciences, Imperial College School of Medicine, London SW7 2AZ, UK.

1. We have investigated the effects of varying flow velocity upon permeability to potassium ions (PK) of single perfused mesenteric microvessels in pithed frogs. 2. PK was estimated using a development of the single bolus microperfusion technique at chosen flow velocities (U) in the range of 150-7000 micron s-1. 3. In thirty-seven out of forty-three vessels, there was a strong positive correlation between PK and U. Average values (median) for PK (micron s-1) were related to U (micron s-1) by the expression: PK = 0.0043U + 4.05 (n = 43). 4. The correlation between PK and U was independent of microvascular pressure (and hence fluid filtration) over the range of 5-70 cmH2O. 5. The correlation between PK and U was independent of the potassium concentration in the bolus over the range of 2-40 mmol l-1 and of the direction of the potassium flux through the capillary walls.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008839	Microelectrodes	Electrodes with an extremely small tip, used in a voltage clamp or other apparatus to stimulate or record bioelectric potentials of single cells intracellularly or extracellularly. (Dorland, 28th ed)	Electrodes, Miniaturized,Electrode, Miniaturized,Microelectrode,Miniaturized Electrode,Miniaturized Electrodes
D011188	Potassium	An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
D011894	Rana pipiens	A highly variable species of the family Ranidae in Canada, the United States and Central America. It is the most widely used Anuran in biomedical research.	Frog, Leopard,Leopard Frog,Lithobates pipiens,Frogs, Leopard,Leopard Frogs
D011896	Rana temporaria	A species of the family Ranidae occurring in a wide variety of habitats from within the Arctic Circle to South Africa, Australia, etc.	European Common Frog,Frog, Common European,Common European Frog,Common Frog, European,European Frog, Common,Frog, European Common
D001783	Blood Flow Velocity	A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.	Blood Flow Velocities,Flow Velocities, Blood,Flow Velocity, Blood,Velocities, Blood Flow,Velocity, Blood Flow
D002199	Capillary Permeability	The property of blood capillary ENDOTHELIUM that allows for the selective exchange of substances between the blood and surrounding tissues and through membranous barriers such as the BLOOD-AIR BARRIER; BLOOD-AQUEOUS BARRIER; BLOOD-BRAIN BARRIER; BLOOD-NERVE BARRIER; BLOOD-RETINAL BARRIER; and BLOOD-TESTIS BARRIER. Small lipid-soluble molecules such as carbon dioxide and oxygen move freely by diffusion. Water and water-soluble molecules cannot pass through the endothelial walls and are dependent on microscopic pores. These pores show narrow areas (TIGHT JUNCTIONS) which may limit large molecule movement.	Microvascular Permeability,Permeability, Capillary,Permeability, Microvascular,Vascular Permeability,Capillary Permeabilities,Microvascular Permeabilities,Permeabilities, Capillary,Permeabilities, Microvascular,Permeabilities, Vascular,Permeability, Vascular,Vascular Permeabilities
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D004594	Electrophysiology	The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
D005070	Evans Blue	An azo dye used in blood volume and cardiac output measurement by the dye dilution method. It is very soluble, strongly bound to plasma albumin, and disappears very slowly.	Azovan Blue,C.I. 23860,C.I. Direct Blue 53,Evan's Blue,Blue, Azovan,Blue, Evan's,Blue, Evans,Evan Blue