砷对孵育组织匀浆巯基的影响——砷对巯基的假性保护效应

Effects of Arsenic on Thiol-group of tissue-HOmogenate in Incubation —A False Protective Phenomenon of Arsenic to Active Thiol-group

:对砷在组织匀浆巯基的作用 ,用组织匀浆由新鲜组织在 p H8的磷酸盐缓冲液中用匀浆器制备 ,加不同量砷后 37°C孵育 3h。在胰腺新鲜匀浆巯基均值为 2 .78μg/1 0 mg组织 ,未加砷及加砷孵育样本分别为 1 .45和 2 .1 5μg/1 0 mg组织。显示在孵育过程中巯基下降 ,而加砷可减轻巯基下降 ,在胰腺其保护率为 58.5%。此现象也见于肝、心脏、肾、肺、脾、脑和肌肉 ,保护率范围为 9.37%± 8.0 3%～ 2 1 .0 7%± 1 0 .0 9%。进一步研究表明在肠糜、胰和唾液腺匀浆中 ,此率随着砷浓度升高而上升。但用沸水浴处理后此现象消失。提示在正常生理条件下匀浆孵育期间一些反应可消耗巯基 ,这些反应可为砷抑制。砷的这种抑制反应可导致巯基的生理效应受抑 ,这种对巯基有害的效应 ,我们称其为“

The aim of this study was to research the effects of arsenic on the thiol-group of tissue-homogenate.The homogenate for studying was preared from fresh tissue by homogenize in pH 8 buffer solution of phosphate.Then taken different dose of arsenic into the homogenate,and incubated at 37°C for three hours.In pancreas,the mean of thiol-group in fresh homogenate was 2.78 μg/10 mg tissue,and those of the groups incubated of non-arsenic and adding arsenic were 1.45 and 2.15 μg,respectively.It showed that the thiol-group reduced in incubation and the wastage could be decreased by adding arsenic,with a protective rate of 58.5% in pancreas.The phenomenon was also found in live,heart,kidney,lung,spleen brain and muscle,with a ranged of 9.37%±8.03%～21.07%±10.09% of protective rate.Further study showed that this rate increased with the arsenic level rising in intraintestinal chyme and homogenate of pancreas and sialaden.The phenomenon was disappeared when the homogenate treated by boiling bath.It suggested that some biochemical reactions could use up thiol-group during the incubation of the homogenate in normal physiology,and that those reactions might be inhibition by arsenic.This suppresion reaction of arsenic could result in failure in physiological effect of thiol-group.In fact,it is a harmful effect for thiol-group.We name it 'false protective Phenomenon'.