Ion dependence of cystine and lysine uptake by rat renal brush-border membrane vesicles.
Ion dependence of cystine and lysine uptake by rat renal brush-border membrane vesicles.
复制标题
大鼠肾刷状缘膜囊泡摄取胱氨酸和赖氨酸的离子依赖性。
DOI：
10.1016/0005-2736(92)90062-q
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Segal,S
中科院分区：
文献类型：
--
作者：
McNamara,PD;Rea,CT;Segal,S
The shared transport system for uptake ofl-cystine andl-lysine was examined in isolated rat renal brush-border membrane vesicles for the ionic requirements for activation of the system. No requirement for sodium was seen for either cystine or lysine influx. However, the efflux of lysine from the vesicle was stimulated by Na+. Therefore, the transport system appears to be asymmetric in its requirement for sodium. Two different divalent cations were used in the membrane isolations which resulted in different responses of cystine uptake to the electrogenic movement of K+out of the vesicle. Membranes prepared by Mg-aggregation showed no stimulation of cystine influx by the imposition of a transient interior negative potential while vesicles prepared by Ca-aggregation did respond to electrogenic stimulation by an outwardly directed K-diffusion potential in the presence of valinomycin. Lysine influx was stimulated by electrogenic potassium efflux in both Mg-prepared and Ca-prepared membranes. No difference in sodium requirement for cystine influx was seen between the vesicles isolated by different cation-aggregation methods.
