Grachev S A, Kropachev E V, Litvjakova G I
St Petersburg Nuclear Physics Institute, Russian Academy of Sciences, Russia.
Int J Radiat Biol. 1995 Nov;68(5):543-51. doi: 10.1080/09553009514551531.
The radiation chemical yields of 5-hydroxy-5,6-dihydrouracil and uracil were measured on radiolysis of N2O-saturated solutions containing I mmol dm-3 poly(U) and were found to be 0.04 and 0.31 mumol J-1 respectively. From the 5-hydroxy-5,6-dihydrouracil yield in the presence of cysteamine and 2-mercaptoethanol, it is shown that only 20% of the OH-radicals, which attack poly(U) results in the formation of 5-hydroxy uracil adducts. It has been proposed that as yet unknown reducing radicals are formed in addition to known reducing radicals (the 5-OH-adducts of uracil, the H-adducts of uracil, and sugar radicals) as a result of the reaction of OH-radicals with poly(U).
在对含有1 mmol dm⁻³聚尿苷酸（poly(U)）的N₂O饱和溶液进行辐解时，测定了5-羟基-5,6-二氢尿嘧啶和尿嘧啶的辐射化学产率，发现分别为0.04和0.31 μmol J⁻¹。根据在半胱胺和2-巯基乙醇存在下5-羟基-5,6-二氢尿嘧啶的产率表明，攻击聚尿苷酸的OH自由基中只有20%会导致5-羟基尿嘧啶加合物的形成。有人提出，由于OH自由基与聚尿苷酸的反应，除了已知的还原自由基（尿嘧啶的5-OH加合物、尿嘧啶的H加合物和糖自由基）外，还会形成尚未知晓的还原自由基。
