Yamaoka K, Ishii K, Edamatsu R, Ito T, Mori A
Radiation Safety Group, Central Research Institute of Electric Power Industry, Tokyo, Japan.
Physiol Chem Phys Med NMR. 1994;26(4):323-8.
This study examines the influence of low dose X-irradiation on the structure and transport function of cell membranes of rat cerebral cortex. We found that unlike high dose irradiation which promotes membrane damage, low dose irradiation stimulates the SH group of membrane proteins and enhances the ability to control the membrane transport mechanism as reflected by an increase in Na+, K(+)-ATPase activity. The concentration of cysteine (Cys) significantly increased at 25-100 cGy and the concentration of cystine (Cys-Cys) significantly decreased at 25 cGy. It showed no dose dependent changes in tyrosine (Tyr), phenylalanine (Phe) and glycine (Gly). Similarly phospholipid and cholesterol levels were unchanged. Na+, K(+)-ATPase activities significantly decreased at 100 cGy or higher but significantly increased at doses of 25 and 50 cGy.
本研究考察了低剂量X射线辐射对大鼠大脑皮质细胞膜结构及转运功能的影响。我们发现，与促进膜损伤的高剂量辐射不同，低剂量辐射可刺激膜蛋白的巯基，并增强控制膜转运机制的能力，这表现为Na+、K(+)-ATP酶活性增加。半胱氨酸（Cys）浓度在25 - 100 cGy时显著升高，胱氨酸（Cys-Cys）浓度在25 cGy时显著降低。酪氨酸（Tyr）、苯丙氨酸（Phe）和甘氨酸（Gly）未表现出剂量依赖性变化。同样，磷脂和胆固醇水平也未改变。Na+、K(+)-ATP酶活性在100 cGy及以上时显著降低，但在25和50 cGy剂量时显著升高。
