title: Heterogeneity of hypotonically loaded rat erythrocyte populations as detected by counter-current distribution in aqueous polymer two-phase systems.
abstract: Carrier rat erythrocytes loaded with exogenous substances ([125I] carbonic anhydrase) by hypotonic-isotonic dialysis become heterogeneous cell populations that can be fractionated using the counter-current distribution (CCD) technique. Two well-defined low- and high-partition ratio, G, subpopulations are obtained in charge-sensitive dextran-polyethylene glycol two-phase systems. The low-G subpopulation, which contains the most fragile and surface-altered cells, as deduced from their osmotic fragility curves and partition behaviour, respectively, presents a high amount of exogenous substance incorporated (134.6 cpm/10(6) cells). The high-G subpopulation, that contains cells similar to the control or isotonically dialyzed cells presents a lower amount of exogenous substance incorporated (69.8 cpm/10(6) cells). Cells in this high-G subpopulation seem to be fractionated, like the controls, according to ageing as suggested by the decline of the pyruvate kinase specific activity from the left- to the right-hand side of the CCD profile.
authors.affiliation: Departmento de Bioquímica y Biología Molecular, Universidad de Alcalá, Madrid, Spain.
authors.forename: M T
authors.initials: MT
authors.lastname: Pérez
authors.forename: F J
authors.initials: FJ
authors.lastname: Alvarez
authors.forename: A I
authors.initials: AI
authors.lastname: García-Pérez
authors.forename: L
authors.initials: L
authors.lastname: Lucas
authors.forename: M C
authors.initials: MC
authors.lastname: Tejedor
authors.forename: P
authors.initials: P
authors.lastname: Sancho
mesh_terms: D000818:Animals; D001772:Blood Cell Count; D002256:Carbonic Anhydrases / Q000097:blood; D003377:Countercurrent Distribution; D003956:Dialysis; D004912:Erythrocytes / Q000502:physiology*; D006801:Humans; D007038:Hypotonic Solutions; D008297:Male; D009996:Osmotic Fragility; D011108:Polymers; D051381:Rats; D017208:Rats, Wistar
chemical_list: D007038:Hypotonic Solutions; D011108:Polymers; D002256:Carbonic Anhydrases