Canine RBC osmotic tolerance and membrane permeability
Source: Cryobiology, Volume 44, Number 3, June 2002 , pp. 258-268(11)
Publisher: Academic Press
The objective of this study was to determine the cryobiological characteristics of canine red blood cells (RBC). These included the hydraulic conductivity (Lp), the permeability coefficients (Ps) of common cryoprotectant agents (CPAs), the associated reflection coefficient(), the activation energies (Ea) ofLp andPs and the osmotic tolerance limits. By using a stopped-flow apparatus, the changes of fluorescence intensity emitted by intracellularly entrapped 5-carboxyfluorescein diacetate (CFDA) were recorded when cells were experiencing osmotic volume changes. After the determination of the relationship between fluorescence intensity and cell volume, cell volume changes were calculated. These volume changes were used in three-parameter fitting calculations to determine the values ofLp,Ps, and for common CPAs. These volume measurements and data analyses were repeated at three different temperatures (22, 14, 7 °C). Using the Arrhenius equation, the activation energies ofLp andPs in the presence of CPAs were determined. The osmotic tolerance limits for canine RBC were determined by measuring the percentage of free hemoglobin in NaCl solutions with various osmolalities compared to that released by RBC incubated in double distilled water. The upper and lower osmotic tolerance limits were found to be 150 mOsm (1.67Viso) and 1200 mOsm (0.45Viso), respectively. These parameters were then used to calculate the amount of non-permeating solute needed to keep cell volume excursions within the osmotic tolerance limits during CPA addition and removal.
© 2002 Elsevier Science (USA)
Document Type: Research article
Affiliations: 1: Comparative Medicine Center and Research Animal Diagnostic Laboratory, College of Veterinary Medicine, University of Missouri, 1600 East Rollins Road, E-109, Columbia, MO 65211, USA 2: Department of Veterinary Pathobiology, School of Veterinary Medicine, Purdue University, West Lafayette, IN, USA
Publication date: 2002-06-01