Effect of aldosterone on /sup 86/Rb fluxes in cultured kidney cells (A6)

Journal Article · Fri Jan 01 04:00:00 EST 1988 · Physiol. Chem. Phys. Med. NMR; (United States)

OSTI ID:6804944

Fidelman, M L; Duncan, R L; Watlington, C O

This study was designed to evaluate the relative contributions of hormone induced changes in active and passive K+ transport in an epithelial cell line in continuous culture derived from toad kidney (A6) using /sup 86/Rb as a tracer for measuring unidirectional K+ fluxes. The effects of 24 h exposure to aldosterone (A) and aldosterone plus insulin (A+I) on unidirectional K+ fluxes were evaluated under short-circuited conditions and under open circuit conditions. In epithelia exposed to A, a small but significant amount of active K+ secretion was found, although it was not significantly greater than in control epithelia. The bidirectional fluxes in both A and A+I treated epithelia, under short-circuited conditions, increased by a similar amount over control values indicating an increase in apparent permeability of passive transepithelial K+ transport. Under open circuit conditions, A stimulated net K+ transport by about 5-fold over controls. The increase in K+ secretion produced by A under open circuit conditions could be explained by the combined effects of an increase in transepithelial K+ permeability and an increase in the transepithelial electrical potential difference (PD). The presence of I produced no additional effects to that of A on K+ transport under the conditions used in this study. It is concluded that the substantial increase in K+ secretion induced in A6 cells by 24 h exposure to A is primarily passive in nature. It is possible that the changes in both PD and transepithelial K+ permeability, which can account for the observed increase in K+ secretion, are secondary to the stimulation of active Na+ transport.

• Research Organization: Virginia Commonwealth Univ., Richmond (USA)
• OSTI ID: 6804944
• Journal Information: Physiol. Chem. Phys. Med. NMR; (United States), Journal Name: Physiol. Chem. Phys. Med. NMR; (United States) Vol. 20:1; ISSN PCPNE
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
ALDEHYDES
ALDOSTERONE
ALKALI METAL COMPOUNDS
ALKALI METAL ISOTOPES
AMPHIBIANS
ANIMAL TISSUES
ANIMALS
AQUATIC ORGANISMS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BODY
CELL CONSTITUENTS
CELL CULTURES
CELL MEMBRANES
CORTICOSTEROIDS
DAYS LIVING RADIOISOTOPES
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
EPITHELIUM
FROGS
HORMONES
HYDROXY COMPOUNDS
INSULIN
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KETONES
KIDNEYS
MEMBRANE TRANSPORT
MEMBRANES
MINERALOCORTICOIDS
MINUTES LIVING RADIOISOTOPES
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANS
PEPTIDE HORMONES
PERMEABILITY
PHYSICAL PROPERTIES
POTASSIUM COMPOUNDS
PREGNANES
RADIOISOTOPES
RUBIDIUM 86
RUBIDIUM ISOTOPES
STEROIDS
TISSUES
TRACER TECHNIQUES
VERTEBRATES