Intracellular free zinc and zinc buffering in human red blood cells

Zn2+ has been allowed to equilibrate across the red cell membrane using two agents that increase membrane permeability to this ion: the ionophore A23187 and the specific carrier ethylmaltol. Extracellular free Zn2+ was controlled with EGTA (1,2-di(2-aminoethoxy)ethane-NNN'N'tetra-acetic ac...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of membrane biology 1991-07, Vol.123 (1), p.63-71
Main Author: SIMONS, T. J. B
Format: Article
Language:English
Subjects:
binding
Binding Sites
Biological and medical sciences
Buffers
Calcimycin - pharmacology
Cell Membrane Permeability
Cell physiology
characterization
Egtazic Acid - pharmacology
Erythrocyte Membrane - metabolism
erythrocytes
Erythrocytes - metabolism
Fundamental and applied biological sciences. Psychology
hemoglobin
Humans
Magnesium - pharmacology
man
Molecular and cellular biology
Pyrones - pharmacology
zinc
Zinc - blood
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Zn2+ has been allowed to equilibrate across the red cell membrane using two agents that increase membrane permeability to this ion: the ionophore A23187 and the specific carrier ethylmaltol. Extracellular free Zn2+ was controlled with EGTA (1,2-di(2-aminoethoxy)ethane-NNN'N'tetra-acetic acid] buffers, except in the case of ethylmaltol, which itself acts as a buffer. Measurement of cellular zinc content at different levels of free Zn2+ facilitated the study of intracellular Zn2+ binding. It was also possible to estimate intracellular free Zn2+ concentration in untreated cells using a "null-point" technique. Intracellular zinc was found to consist of an inexchangeable component of about 129 mumol/10(13) cells and an exchangeable component of 6.7 +/- 1.5 mumol/10(13) cells, with a free concentration of about 2.4 x 10(-11) M. The main component of Zn2+ buffering is hemoglobin, with a dissociation constant of about 2 x 10(-8) M.
ISSN:0022-2631
1432-1424
DOI:10.1007/bf01993964