Bilayer balance and regulation of red cell shape changes
β Scribed by Mohandas, Narla ;Greenquist, Alfred C. ;Shohet, Stephen B.
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1978
- Tongue
- English
- Weight
- 365 KB
- Volume
- 9
- Category
- Article
- ISSN
- 0091-7419
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β¦ Synopsis
Abstract
Discocytic human red cells undergo discocyteβechinocyte and discocytestomatocyte transformations under the action of a wide variety of lipidβsoluble anionic and cationic agents respectively. These shape transformations are explained by the bilayer couple hypothesis of Sheetz and Singer to be the result of preferential distribution of the anionic agents in the outer half of the bilayer and the cationic agents in the inner half of the bilayer. We demonstrate that echinocytogenic effects indeed occur when the naturally occurring phospholipid lysophosphatidylcholine (LPC) is localized in the outer half of the bilayer, and stomatocytogenic effects occur when LPC is in the inner half. However, in contrast to the bilayer couple hypothesis, our results show that simple equivalent membrane surface area expansion on each layer is insufficient to maintain the discocytic shape and there exists a differential concentration effect of LPC on the two halves of the bilayer.
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