Kinetics of uptake and deacetylation of N-acetylcysteine by human erythrocytes

2007 ◽  
Vol 39 (9) ◽  
pp. 1698-1706 ◽  
Author(s):  
Julia E. Raftos ◽  
Stephney Whillier ◽  
Bogdan E. Chapman ◽  
Philip W. Kuchel
Keyword(s):  
Human Erythrocytes ◽  
Kinetics Of Uptake ◽  
Kinetics Of

scholarly journals Influence of fluorophore and linker length on the localization and trafficking of fluorescent sterol probes

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jarmila Králová ◽  
Michal Jurášek ◽  
Lucie Mikšátková ◽  
Anna Marešová ◽  
Jan Fähnrich ◽  
...  
Keyword(s):  
Genetic Mutation ◽  
Cell Permeability ◽  
Specific Cell ◽  
Cell Compartments ◽  
Intracellular Compartments ◽  
Resolution Imaging ◽  
Intracellular Labelling ◽  
Kinetics Of Uptake ◽  
Kinetics Of ◽  
Derivatives Of

AbstractFluorescent sterol probes, comprising a fluorophore connected to a sterol backbone by means of a linker, are promising tools for enabling high-resolution imaging of intracellular cholesterol. In this study, we evaluated how the size of the linker, site of its attachment and nature of the fluorophore, affect the localization and trafficking properties of fluorescent sterol probes. Varying lengths of linker using the same fluorophore affected cell penetration and retention in specific cell compartments. A C-4 linker was confirmed as optimal. Derivatives of heterocyclic sterol precursors attached with identical C-4 linker to different fluorophores at diverse positions also showed significant differences in their binding properties to various intracellular compartments and kinetics of trafficking. Two novel red-emitting probes with good cell permeability, fast intracellular labelling and slightly different distribution displayed very promising characteristics for sterol probes. These probes also strongly labelled endo/lysosomal compartment in cells with pharmacologically disrupted cholesterol transport, or with a genetic mutation of cholesterol transporting protein NPC1, that overlapped with filipin staining of cholesterol. Overall, the present study demonstrates that the physicochemical properties of the fluorophore/linker pairing determine the kinetics of uptake and distribution and subsequently influence the applicability of final probes.

scholarly journals Determination of the steady-state turnover rates of the metabolically active pools of phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate in human erythrocytes

1989 ◽  
Vol 259 (3) ◽  
pp. 893-896 ◽  
Author(s):  
C E King ◽  
P T Hawkins ◽  
L R Stephens ◽  
R H Michell
Keyword(s):  
Steady State ◽  
Rate Constants ◽  
Human Erythrocytes ◽  
Turnover Rates ◽  
Metabolic Fluxes ◽  
Metabolic Pool ◽  
Phosphatidylinositol 4 ◽  
Kinetics Of ◽  
Phosphate Groups

When intact human erythrocytes are incubated at metabolic steady state in a chloride-free medium containing [32P]Pi, there is rapid labelling of the gamma-phosphate of ATP, followed by a slower labelling of the monoester phosphate groups of phosphatidylinositol 4-phosphate (PtdIns4P) and phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] [King, Stephens, Hawkins, Guy & Michell (1987) Biochem. J. 244, 209-217]. We have analysed the early kinetics of the labelling of these phosphate groups, in order to determine: (a) the steady-state rates of the interconversions of phosphatidylinositol, PtdIns4P and PtdIns(4,5)P2; and (b) the fractions of the total cellular complement of PtdIns4P and PtdIns(4,5)P2 that participate in this steady-state turnover. The experimental data most closely fit a pattern of PtdIns4P and PtdIns(4,5)P2 turnover in which one-quarter of the total cellular complement of each lipid is in the metabolic pool that participates in rapid metabolic turnover, with rate constants of 0.028 min-1 for the interconversion of PtdIns and PtdIns4P, and of 0.010 min-1 for the PtdIns4P/PtdIns(4,5)P2 cycle. These rate constants represent metabolic fluxes of approx. 2.1 nmol of lipid/h per ml of packed erythrocytes between PtdIns and PtdIns4P and of approx. 5.7 nmol/h per ml of cells between PtdIns4P and PtdIns(4,5)P2.

A note on the kinetics of uptake of d-glucose by the food yeast, Candida utilis

1976 ◽  
Vol 111 (1-2) ◽  
pp. 193-194 ◽  
Author(s):  
James A. Barnett ◽  
Anthony P. Sims
Keyword(s):  
Candida Utilis ◽  
Food Yeast ◽  
Kinetics Of Uptake ◽  
Kinetics Of

Sodium Exchange in the Frog Heart Ventricle

1957 ◽  
Vol 191 (3) ◽  
pp. 487-492 ◽  
Author(s):  
John A. Johnson
Keyword(s):  
Extracellular Space ◽  
Cell Membranes ◽  
Frog Heart ◽  
Heart Ventricle ◽  
Radioactive Sodium ◽  
Kinetics Of Uptake ◽  
Kinetics Of ◽  
Uptake And Release ◽  
Sodium Exchange

The isolated frog heart ventricle was used to study the kinetics of uptake and release of radioactive sodium. Sucrose was used as an extracellular space indicator. A flux of sodium across the ventricle cell membranes of 15 x 10–12 m/cm2 sec. was calculated from the data.

Sign in / Sign up

Export Citation Format

Share Document