胆固醇对人红细胞非电解质膜转运的影响：核磁共振磁化转移研究。

Cholesterol effects on nonelectrolyte membrane transport in human erythrocytes: NMR magnetization transfer studies.

作者信息

Nouri-Sorkhabi M H, Chapman B E, Sullivan D R, Kuchel P W

机构信息

Department of Biochemistry, University of Sydney, N.S.W. Australia.

出版信息

Magn Reson Med. 1994 Oct;32(4):505-10. doi: 10.1002/mrm.1910320413.

DOI:10.1002/mrm.1910320413

PMID:7997117

Abstract

The cholesterol content of human erythrocytes was altered by incubating them with sonicated dispersions of cholesterol/phosphatidylcholine at 37 degrees C. 31P NMR saturation transfer experiments were used to measure the rate constant for efflux of dimethyl methylphosphonate (DMMP) from the cells, and thereby gain an estimate of the permeability coefficient. It was shown that up to 39% depletion of membrane cholesterol (cholesterol/phospholipid molar ratio of 0.46) increased the efflux rate constant and permeability coefficient of DMMP 1.55- and 1.86-fold, respectively. Enrichment of the membranes with cholesterol by 45% (cholesterol/phospholipid molar ratio of 1.57) on the other hand, decreased the efflux rate constant and permeability coefficient 1.63- and 1.79-fold, respectively. It was concluded that DMMP may be used as a probe molecule to study the functional consequences of changes in the lipid composition of erythrocytes in diseases that are associated with disorders of lipid metabolism.

摘要

通过将人类红细胞与胆固醇/磷脂酰胆碱的超声分散液在37℃下孵育，改变了红细胞的胆固醇含量。利用31P NMR饱和转移实验测量了二甲基甲基膦酸酯（DMMP）从细胞中流出的速率常数，从而估算出渗透系数。结果表明，膜胆固醇消耗高达39%（胆固醇/磷脂摩尔比为0.46）时，DMMP的流出速率常数和渗透系数分别增加了1.55倍和1.86倍。另一方面，膜胆固醇含量增加45%（胆固醇/磷脂摩尔比为1.57）时，流出速率常数和渗透系数分别降低了1.63倍和1.79倍。得出的结论是，DMMP可作为一种探针分子，用于研究与脂质代谢紊乱相关疾病中红细胞脂质组成变化的功能后果。