Modulation of human erythrocyte Ca2+-ATPase activity by glycerol: the role of calmodulin.
Biochemistry (Mosc)
; 71(8): 900-5, 2006 Aug.
Article
em En
| MEDLINE
| ID: mdl-16978154
ABSTRACT
The effect of an intracellular cryoprotectant glycerol on human erythrocyte Ca2+-ATPase activity and possible involvement of calmodulin in the regulation of Ca2+-pump under these conditions were investigated. The experiments were carried out using saponin-permeabilized cells and isolated erythrocyte membrane fractions (white ghosts). Addition of rather low concentrations of glycerol to the medium increased Ca2+-ATPase activity in the saponin-permeabilized cells; the maximal effect was observed at 10% glycerol. Subsequent increase in glycerol concentrations above 20% was accompanied by inhibition of Ca2+-ATPase activity. Lack of stimulating effect of glycerol on white ghost Ca2+-ATPase may be attributed to removal of endogenous compounds regulating activity of this ion transport system. Inhibitory analysis using R24571 revealed that activation of Ca2+-ATPase by 10% glycerol was observed only in the case of inhibitor administration after modification of cells with glycerol; in the case of inhibitor addition before erythrocyte contact with glycerol, this phenomenon disappeared. These data suggest the possibility of regulation of human erythrocyte Ca2+-ATPase by glycerol; this regulatory effect may be attributed to both glycerol-induced structural changes in the membrane and also involvement of calmodulin in modulation of catalytic activity of the Ca2+-pump.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Calmodulina
/
ATPases Transportadoras de Cálcio
/
Crioprotetores
/
Eritrócitos
/
Glicerol
Limite:
Humans
/
Male
Idioma:
En
Revista:
Biochemistry (Mosc)
Ano de publicação:
2006
Tipo de documento:
Article
País de afiliação:
Ucrânia