Aviram A, Aviram I
Department of Biochemistry, Faculty of Life Sciences, Tel-Aviv University, Israel.
Cell Calcium. 1989 Feb-Mar;10(2):115-24. doi: 10.1016/0143-4160(89)90051-1.
The involvement of calcium in N,N'-dicyclohexylcarbodiimide (DCCD)-mediated stimulation of guinea pig neutrophils was investigated. Exposure to DCCD resulted in a fast though moderate elevation of cytosolic calcium concentration. Exchange experiments indicated that DCCD enhanced 45Ca2+ efflux without affecting uptake of the radioisotope from the medium. Plasma membranes isolated from DCCD-stimulated cells failed to support ATP-dependent 45Ca2+ uptake indicating inhibition of their Ca-ATPase. The finding that the enhanced efflux of 45Ca2+ depended on the presence of Na+ ions in the medium implicated a Na+/Ca2+ exchanger in efflux of the ion observed in DCCD-stimulated neutrophils. This is the first indication for the participation of this carrier in calcium homeostasis in stimulated neutrophils. Experiments carried out with 14C-DCCD indicated covalent binding of the reagent to 20 and 150 Kd membrane proteins.
研究了钙在N，N'-二环己基碳二亚胺（DCCD）介导的豚鼠中性粒细胞刺激中的作用。暴露于DCCD会导致胞质钙浓度快速但适度升高。交换实验表明，DCCD增强了45Ca2+外流，而不影响从培养基中摄取放射性同位素。从DCCD刺激的细胞中分离出的质膜无法支持ATP依赖性的45Ca2+摄取，表明其钙ATP酶受到抑制。45Ca2+外流增强依赖于培养基中Na+离子的存在这一发现表明，在DCCD刺激的中性粒细胞中观察到的离子外流涉及Na+/Ca2+交换器。这是该载体参与刺激的中性粒细胞钙稳态的首个迹象。用14C-DCCD进行的实验表明该试剂与20和150 Kd的膜蛋白共价结合。
