Modulation of RBC volume distributions by oxidants (phenazine methosulfate and tert-butyl hydroperoxide): role of Gardos channel activation.
A study was made comparing the effects of two oxidants--phenazine methosulfate (50-1500 microM)+10 mM ascorbate and t-butyl hydroperoxide (1-3 mM)--on the volume-related parameters of normal human red blood cells. Incubation with either oxidative system for 20-30 min resulted in red blood cell density and osmotic resistance distribution shifts. Treatment with the phenazine methosulfate+ascorbate system in the presence of Ca(2+) led to cell shrinking, with the maximum effect being more than 20%. In contrast, under the same conditions, t-BHP caused cell swelling by up to 15%. Modification of the suspending medium (Ca(2+) removing, clotrimazole addition, or enrichment with K(+)) modulated the redistribution effects, suggesting that they were mediated to some extent by Gardos channel activation. These findings are important for understanding how oxidants modulate RBC cation channels.
Lisovskaya
Irina L
IL
National Scientific Centre for Hematology, Novyi Zykovsky pr. 4a, Moscow, Russia. irene_l@mail.ru
Shcherbachenko
Irina M
IM
Volkova
Rimma I
RI
Tikhonov
Vladimir P
VP
D002118:Calcium / Q000378:metabolism; D048429:Cell Size; D004912:Erythrocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D008773:Methylphenazonium Methosulfate / Q000494:pharmacology*; D009997:Osmotic Pressure; D016877:Oxidants / Q000494:pharmacology*; D010084:Oxidation-Reduction / Q000187:drug effects; D024681:Potassium Channels, Calcium-Activated / Q000378:metabolism*; D020122:tert-Butylhydroperoxide / Q000494:pharmacology*
D016877:Oxidants; D024681:Potassium Channels, Calcium-Activated; D008773:Methylphenazonium Methosulfate; D020122:tert-Butylhydroperoxide; D002118:Calcium