title: Comparative nuclear magnetic resonance studies of diffusional water permeability of red blood cells from sheep and cow.
abstract: 1. The diffusional water permeability (p) of sheep and cow red blood cell (RBC) membrane has been monitored by a doping nuclear magnetic resonance (NMR) technique on control cells and following inhibition with p-chloromercuribenzene sulfonate (PCMBS). 2. There were no significant differences in the water permeability of sheep and cow RBCs, the values of p being around 3 x 10(-3) cm/sec at 20 degrees C and 5 x 10(-3) cm/sec at 37 degrees C. 3. Systematic studies of the effects of PCMBS on water diffusion indicated that in both species the maximal inhibition is reached in 60-90 min at 37 degrees C with 1 mM PCMBS. 4. The degree of inhibition increased as the temperature of measurement decreased, regardless of PCMBS concentration and incubation time. 5. The values of maximal inhibition ranged from 60-70% at 20 degrees C to 50-60% at 37 degrees C in the case of sheep RBCs, and from 45-55% at 20 degrees C to 40-50% at 37 degrees C in the case of cow RBCs. 6. The basal permeability to water of sheep RBCs was estimated as 1.0 x 10(-3) cm/sec at 20 degrees C and 2.2 x 10(-3) cm/sec at 37 degrees C, and that of cow RBCs as 1.6 x 10(-3) cm/sec at 20 degrees C and 2.7 x 10(-3) cm/sec at 37 degrees C. 7. In both species the activation energy of water diffusion was around 23 kJ/mol in control cells and reached values of around 30 kJ/mol after incubation with PCMBS in conditions of maximal inhibition of water diffusion.(ABSTRACT TRUNCATED AT 250 WORDS)
authors: Department of Cell and Molecular Biology, University of Medicine and Pharmacy-Cluj-Napoca, Romania.
authors: G
authors: G
authors: Benga
authors: T
authors: T
authors: Borza
authors: O
authors: O
authors: Popescu
authors: D
authors: D
authors: Poruţiu
authors: H
authors: H
authors: Matei
mesh_terms: D000818:Animals; D002417:Cattle / Q000097:blood*; D002463:Cell Membrane Permeability / Q000502:physiology*; D004058:Diffusion; D004910:Erythrocyte Membrane / Q000378:metabolism*; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D012756:Sheep / Q000097:blood*; D013045:Species Specificity; D014867:Water / Q000378:metabolism*
chemical_list: D014867:Water