Quin2法测定人血小板胞浆游离钙浓度

应用荧光钙指示剂Ｑｕｉｎ２测定胞装游离钙浓度的方法，研究了在不同胞外游离钙浓度［Ｃａ￣（２＋）］＿０下人血小板场急状态时及由凝血四激活后的胞装游离钙浓度［Ｃａ￣（２＋）］＿１的变化．结果显示：凝血的可使负载Ｑｕｉｎ２的人血小板［Ｃａ￣（２＋）］＿１呈现浓度依赖性的短暂升高，且这种作用对［Ｃａ￣（２＋）］＿０有明显的依赖性。该项结果提示凝血酸引起的［Ｃａ￣（２＋）］＿１升高主要来源于外钙内流，部分为内钙释放所致．

赛庚啶对大鼠脑突触体Ca^(2+)水平和Ca^(2+)·Mg^(2+)-ATP酶活性的影响

观察赛庚啶(Cyp)对大鼠脑突触体Ca^(2+)水平和Ca^(2+)·Mg^(2+)-ATP酶活性的影响,以探讨其对脑缺血再灌注损伤的保护作用机理。用Quin2/AM法测定,突触体静息游离Ca^(2+)浓度为88±16μmol·g^(-1)蛋白,1.0,2.5和5.0μmol·L^(-1)的Cyp对其基本无影响。对高K^+所致突触体Ca^(2+)浓度升高有抑制作用但不显著,由185±45μmol·g^(-1)蛋白分别降至182±41、181±41、178±38μmol·g^(-1)蛋白;使突触体Ca^(2+)·Mg^(2+)-ATP酶活性由78±15mmol·h^(-1)·g^(-1)蛋白下降至74±12,70±11和65±8mmol·h^(-1)·g^(-1)蛋白。表明,Cyp是通过抑制Ca^(2+)内流和选择性抑制Ca^(2+)·Mg^(2+)-ATP酶活性,而稳定内质网和腺粒体内Ca^(2+)浓度,从而达到对脑缺血再灌注损伤的保护作用。

The Different Fluorescent Response of Quin 2 to the Binding of Ca^(2+) and La^(3+) and its Application

The fluorescence spectra of Quin 2, (2-[(2-bis-[carboxymethyl] amino-5-methylphenoxy) methyl]-6-methoxy-8-bis [carboxymethyl] aminoquiniline), a Ca2+ probe, were investigated upon incubation with Ca2+ or La3+. The results showed that binding of La3+ to Quin 2 resulted in different fluorescent spectrum from that of Ca2+. Based on this observation, a fluorescent method was developed for simultaneously determination of the dissociation rates of Ca2+ and La3+ from a Ca-La- calmodulin complex (Ca2La2CaM).