Shliakova T G, Sharygin V L, Zorin V V, Chernov G A, Pulatova M K
Radiats Biol Radioecol. 2014 Jan-Feb;54(1):50-6.
Radioprotective properties of indralin were studied at its combined administration with indometophene in the periods optimal for each preparation before acute radiation exposure. Animals were subjected to total radiation on the IGUR installation (137Cs): mice of the strain (CBA x C57B1) F1 at a dose of 9 Gy (LD100/30), purebred dogs--4 Gy (LD100/45). It was established in the experiments on mice that considerable radioprotective effect can be obtained by the use of indralin at a dose that is half the optimal radioprotective dose if it is applied against the background of indometophene administered at its optimal radioprotective dose four days before. The survival of mice increased on the average by 30-35% and provided the same effect of protection as a single indralin at the optimal radioprotective dose (100 mg/kg). The survivability of dogs after the combined application of the two radioprotectors makes up 43% against 14% after application of only indralin at a dose of 5 mg/kg (half the optimal radioprotective dose). Indometophene, along with strengthening the antiradiation activity of indralin at the ineffective (half the optimal) dose, allows the reduction of its undesirable postradiation effects in the hemopoietic tissue. The important role in the mechanism of the antiradiation activity of indometophene and indralin belongs to the increased ribonucleotide reductase activity and induction of the ribonucleotide synthesis that provides effective reparation of the damage to the DNA of the cells in radiosensitive tissues and organs as a result of administration of protective doses of radioprotectors at the optimal doses before radiation exposure.
在急性辐射暴露前，于每种制剂的最佳时期，研究了因屈林与吲哚托芬联合给药时的辐射防护特性。动物在IGUR装置（137Cs）上接受全身辐射：（CBA×C57B1）F1品系小鼠，剂量为9 Gy（LD100/30），纯种犬为4 Gy（LD100/45）。在小鼠实验中发现，如果在辐射前四天以最佳辐射防护剂量给予吲哚托芬的背景下，使用剂量为最佳辐射防护剂量一半的因屈林，可获得显著的辐射防护效果。小鼠的存活率平均提高了30 - 35%，并提供了与最佳辐射防护剂量（100 mg/kg）的单一因屈林相同的保护效果。两种辐射防护剂联合应用后犬的存活率为43%，而仅使用剂量为5 mg/kg（最佳辐射防护剂量的一半）的因屈林时存活率为14%。吲哚托芬除了在无效（最佳剂量的一半）剂量下增强因屈林的抗辐射活性外，还能减少其在造血组织中的不良辐射后效应。吲哚托芬和因屈林抗辐射活性机制中的重要作用在于核糖核苷酸还原酶活性的增加和核糖核苷酸合成的诱导，这使得在辐射暴露前以最佳剂量给予辐射防护剂后，能有效修复放射敏感组织和器官中细胞DNA的损伤。
