Inhibition of Jurkat-T-lymphocyte Na+/H+-exchanger by CD95(Fas/Apo-1)-receptor stimulation

被引：76

作者：

Lang, F ^{[1
]}

Madlung, J ^{[1
]}

Bock, J ^{[1
]}

Lükewille, U ^{[1
]}

Kaltenbach, S ^{[1
]}

Lang, KS ^{[1
]}

Belka, C ^{[1
]}

Wagner, CA ^{[1
]}

Lang, HJ ^{[1
]}

Gulbins, E ^{[1
]}

Lepple-Wienhues, A ^{[1
]}

机构：

[1] Univ Tubingen, Dept Physiol, D-72076 Tubingen, Germany

来源：

PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY | 2000年 / 440卷 / 06期

关键词：

apoptosis; ATP; cell death; cell shrinkage; DNA fragmentation; Lck(56); Src-like kinase;

D O I：

10.1007/s004240000358

中图分类号：

Q4 [生理学];

学科分类号：

071003 ;

摘要：

Mitogenic factors are known to stimulate the Na+/H+-exchanger (NHE), leading to cytosolic alkalinization and/or cell swelling. Conversely, a hallmark of apoptosis is cell shrinkage and CD95-induced apoptosis has been reported to be paralleled by cytosolic acidification. To assess whether the CD95-receptor regulates NHE activity in Jurkat T-lymphocytes, we performed conventional BCECF fluorescence measurements and SNARF flow cytometric analysis (FACS). The recoveries from acidifications following application of butyrate or a NH3 pulse were both abolished by a specific NHE-inhibitor HOE694, indicating that they fully depend on NHE activity. Thus they were taken as a measure of NHE activity. CD95-receptor stimulation caused a cytosolic acidification and blunted the recovery from acidification following application of butyrate or a NH3 pulse. Moreover, the NHE-dependent alkalinization following osmotic cell shrinkage was almost abolished by CD95-receptor stimulation. As apparent from the effect of osmotic cell shrinkage, inhibition of the NHE by CD95-receptor stimulation was absent in Lck(56)-deficient J-CaM 1.6 cells and restored by retransfection of J-CaM 1.6-cells with Lck(56) CD95-receptor stimulation led within 4 h to a decrease of cellular ATP which could contribute to NHE inhibition. Treatment of Jurkat cells with the NHE inhibitor HOE694 accelerated CD95-induced DNA fragmentation. In conclusion, CD95-receptor stimulation inhibits NHE activity through a mechanism that depends directly or indirectly on the activation of the Src-like kinase Lck(56) This effect contributes to CD95-induced cytosolic acidification, DNA fragmentation and cell shrinkage.

引用

页码：902 / 907

页数：6

共 38 条

[1] MODIFIER ROLE OF INTERNAL H+ IN ACTIVATING THE NA+-H+ EXCHANGER IN RENAL MICROVILLUS MEMBRANE-VESICLES [J].