Referenced in: none

Automatically associated channels: Kv10.1

Title: The human red cell voltage-dependent cation channel. Part III: Distribution homogeneity and pH dependence.

Authors: P Bennekou, T L Barksmann, P Christophersen, B I Kristensen

Journal, date & volume: Blood Cells Mol. Dis., 2006 Jan-Feb , 36, 10-4

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/16376587

Abstract
The homogeneity of the distribution of the non-selective voltage-dependent cation channel (the NSVDC channel) in the human erythrocyte, and the pH dependence was investigated. Activation of this channel caused a uniform cellular dehydration, which was characterized by the changes in the erythrocyte osmotic resistance profiles: after 1/2 h of activation, the osmolarity at 50% hemolysis changed from 73 mM (control) to 34 mM NaCl, corresponding to 0.48% and 0.21% NaCl respectively. Unchanging standard deviations show participation of the entire erythrocyte population, which implies an even distribution of the NSVDC channel among the cells. Inactivation of the NSVDC channel with N-ethyl-maleimide (NEM) or blocking of the Cl(-) conductance with NS1652 retarded the migration of the resistance profiles towards lower osmolarities. The NSVDC channel activation was blocked by a decrease of the intracellular -- but not the extracellular -- pH. The apparent pK(A) value for the effect was estimated to be 6.5, and the specific histidine reagent 2.4'-dibromoacetophenone (DBAB) inactivated the NSVDC channel.