Pani A, Obino P, Guarracino P, La Colla P
Experientia. 1994 Jan 15;50(1):29-33. doi: 10.1007/BF01992045.
4,6-dimethyl-2-amino-3,4,5-trimethoxyphenyl-pyrimidine (B-31) is a pyrimidine derivative previously reported to arrest the mitotic cycle of mammalian cells in metaphase. In the present study it is shown that B-31 also acts as a specific inhibitor of the cellular uptake of nucleosides. The uptake of purinic and pyrimidinic nucleosides is inhibited by 80-90% at concentrations in the range 5-20 micrograms/ml, whereas those of nucleobases, leucine, choline and glucose are unaltered at the maximum nontoxic dose of B-31 (25 micrograms/ml). Various mammalian (human, monkey and murine) and avian cell are equally sensitive to the inhibition of nucleoside transport. The antimitotic effect of B-31, by contrast, is species-specific: human cells are the most sensitive whereas monkey and chicken fibroblasts appear resistant to this effect. Both effects can be reversed by removal of B-31 from the medium; inhibition of nucleoside transport can also be reversed by high doses of the nucleosides themselves.
4,6 - 二甲基 - 2 - 氨基 - 3,4,5 - 三甲氧基苯基嘧啶（B - 31）是一种嘧啶衍生物，此前有报道称其能使哺乳动物细胞的有丝分裂周期停滞在中期。在本研究中发现，B - 31还可作为核苷细胞摄取的特异性抑制剂。在5 - 20微克/毫升的浓度范围内，嘌呤核苷和嘧啶核苷的摄取被抑制80 - 90%，而在B - 31的最大无毒剂量（25微克/毫升）下，核苷碱基、亮氨酸、胆碱和葡萄糖的摄取未发生改变。各种哺乳动物（人、猴和鼠）及禽类细胞对核苷转运抑制的敏感性相同。相比之下，B - 31的抗有丝分裂作用具有物种特异性：人类细胞最敏感，而猴和鸡的成纤维细胞对此作用似乎具有抗性。通过从培养基中去除B - 31，这两种作用均可逆转；高剂量的核苷本身也可逆转对核苷转运的抑制作用。
