Clark M A, Cook M, Mong S, Hogaboom G K, Shorr R, Stadel J, Crooke S T
Life Sci. 1984 Jul 23;35(4):441-8. doi: 10.1016/0024-3205(84)90655-6.
Leukotriene C4 (LTC4) has been demonstrated to induce contraction of the smooth muscle cell line DDT1MF2. A partially purified membrane fraction obtained from these cells exhibited a high affinity binding site for LTC4. Binding of [3H]-LTC4 was saturable, specific and reversible with a dissociation constant (Kd) of 21 +/- 4 nM. The maximum number of binding sites (Bmax) was 55 +/- 5 pmol/mg of protein. Specificity was demonstrated in competition studies in which the Ki of LTC4 against specifically bound [3H]-LTC4 was 12 nM whereas Leukotriene D4 (LTD4) and Leukotriene E4 (LTE4) had a Ki of 38 +/- 4 and 4.7 +/- 0.5 nM respectively. A previously described antagonist of leukotriene-induced smooth muscle contraction PFL 55712 had a Ki of 23 +/- 2 nM as determined by competition binding experiments.
白三烯C4(LTC4)已被证明可诱导平滑肌细胞系DDT1MF2收缩。从这些细胞中获得的部分纯化膜组分对LTC4表现出高亲和力结合位点。[3H]-LTC4的结合具有饱和性、特异性且可逆,解离常数(Kd)为21±4 nM。结合位点的最大数量(Bmax)为55±5 pmol/mg蛋白质。在竞争研究中证明了特异性,其中LTC4对特异性结合的[3H]-LTC4的抑制常数(Ki)为12 nM,而白三烯D4(LTD4)和白三烯E4(LTE4)的Ki分别为38±4和4.7±0.5 nM。通过竞争结合实验确定,先前描述的白三烯诱导的平滑肌收缩拮抗剂PFL 55712的Ki为23±2 nM。