Abstract
Erythrocytes from several different species were exposed to Ca2+ and the bivalent-cation ionophore A23187. The lipid composition, morphology and K+ permeability of the treated cells were investigated. Erythrocytes from human, rat, guinea pig and rabbit (a) showed an increased concentration of 1,2-diacyl-sn-glycerol and enhanced labelling of phosphatidate with 32P, (b) underwent echinocytosis and outward vesiculation, and (c) rapidly released much of their intracellular K+. Pig cells showed only the K+ loss, and ox and sheep (high-K+) cells showed none of these Ca2+-evoked effects. All of the cells underwent stomatocytosis and inward vesiculation when treated externally with Clostridium perfringens phospholipase C. These results support the idea that there is a correlation between the asymmetric insertion of diacylglycerol (or ceramide) into the membrane and the shape-changes leading to microvesiculation, but they indicate that Ca2+-triggered K+ efflux and diacylglycerol production are unrelated events. Erythrocytes of chicken and turkey showed no Ca2+-stimulated K+ efflux. They showed slight ionophore A23187-stimulated vesiculation, but this appeared to be associated with the appearance in the membrane of ceramide rather than of diacylglycerol. Phospholipase C treatment caused very similar changes in morphology and phosphatidate labelling to those seen in mammalian erythrocytes.
Dates
Type | When |
---|---|
Created | 10 years ago (Aug. 10, 2015, 4:08 p.m.) |
Deposited | 3 years, 8 months ago (Nov. 26, 2021, 12:52 p.m.) |
Indexed | 1 year, 2 months ago (June 12, 2024, 1:49 p.m.) |
Issued | 47 years, 11 months ago (Sept. 15, 1977) |
Published | 47 years, 11 months ago (Sept. 15, 1977) |
Published Print | 47 years, 11 months ago (Sept. 15, 1977) |
@article{Allan_1977, title={Calcium ion-dependent diacylglycerol accumulation in erythrocytes is associated with microvesiculation but not with efflux of potassium ions}, volume={166}, ISSN={0264-6021}, url={http://dx.doi.org/10.1042/bj1660495}, DOI={10.1042/bj1660495}, number={3}, journal={Biochemical Journal}, publisher={Portland Press Ltd.}, author={Allan, D and Michell, R H}, year={1977}, month=sep, pages={495–499} }