Steer M L, Baldwin C, Levitzki A
J Biol Chem. 1976 Aug 25;251(16):4930-5.
A method for preparing resealed turkey erythrocyte ghosts is described which utilizes hypotonic lysis and resealing following restoration of isotonicity. The resealed ghosts are isolated above 55% sucrose. The resealed ghosts are shown to be capable of maintaining high intracellular K+ concentrations in the presence of a low K+ extracellular environment. When ATP and an ATP-regenerating system are included during the resealing stage, (R)-(-)-epinephrine- and NaF-stimulated cyclic AMP accumulation, which is linear for 20 min, can be demonstrated. The concentration of (R)-(-)-epinephrine producing a half-maximal response in resealed ghosts is 1.0 +/- 0.4 X 10(-6) M. This is the same as that for (R)-(-)-epinephrine in the intact erythrocyte. The resealed ghosts are impermeable to Ca2+, but Ca2+ inhibition of cyclic AMP accumulation is noted if the divalent cation ionophore. A-23187, is present or if Ca2+ is included during the resealing stage.
本文描述了一种制备重封火鸡红细胞血影的方法,该方法利用低渗裂解并在恢复等渗后进行重封。重封血影在55%以上的蔗糖溶液中分离得到。重封血影在细胞外低钾环境下能够维持较高的细胞内钾离子浓度。当在重封阶段加入ATP和ATP再生系统时,可以证明(R)-(-)-肾上腺素和NaF刺激的环磷酸腺苷(cAMP)积累在20分钟内呈线性。在重封血影中产生半数最大反应的(R)-(-)-肾上腺素浓度为1.0±0.4×10⁻⁶M。这与完整红细胞中(R)-(-)-肾上腺素的浓度相同。重封血影对钙离子是不可渗透的,但如果存在二价阳离子载体A-23187或在重封阶段加入钙离子,则会观察到钙离子对cAMP积累的抑制作用。