Pintado E, Baquero-Leonis D, Conde M, Sobrino F
Departamento de Bioquímica Médica y Biología Molecular, Facultad de Medicina, Universidad de Sevilla, Spain.
Biochem Pharmacol. 1995 Jan 18;49(2):227-32. doi: 10.1016/s0006-2952(94)00401-3.
We have studied the effects of thimerosal, a mercurial compound extensively used as a preservative, as well as other sulfhydryl reagents (e.g. p-hydroxymercurybenzoate, hydrogen peroxide, bromophenacyl bromide, and mercuric chloride) on Ca2+ homeostasis and the redox status of sulfhydryl groups in thymus lymphocytes. They all induced an increase in [Ca2+]i which was blocked with dithiothreitol, suggesting that they act via the oxidation or blockade of sulfhydryl groups. [Ca2+]i increase could be directly related to the effect of the different reagents on cellular protein sulfhydryl content. Experiments with ethidium bromide indicate that the observed rise in [Ca2+]i was not due to a non-specific increase in membrane permeability. Thimerosal differs from the other agents studied in its oxidative properties, which is probably linked to the production of a potent reductor molecule, thiosalicylic acid, which may modulate its oxidative capacity.
我们研究了硫柳汞（一种广泛用作防腐剂的汞化合物）以及其他巯基试剂（如对羟基汞苯甲酸盐、过氧化氢、溴苯甲酰溴和氯化汞）对胸腺淋巴细胞中Ca2+稳态和巯基氧化还原状态的影响。它们均诱导细胞内Ca2+浓度（[Ca2+]i）升高，且该升高被二硫苏糖醇阻断，这表明它们通过氧化或阻断巯基起作用。[Ca2+]i升高可能与不同试剂对细胞蛋白质巯基含量的影响直接相关。用溴化乙锭进行的实验表明，观察到的[Ca2+]i升高并非由于膜通透性的非特异性增加。硫柳汞在氧化特性上与所研究的其他试剂不同，这可能与一种强效还原剂分子硫代水杨酸的产生有关，硫代水杨酸可能会调节其氧化能力。
