Seifert J, Vácha J
Drug Metab Dispos. 1975 Nov-Dec;3(6):430-6.
Utilization of [2-14C]orotic acid for the synthesis of the pyrimidine components of the free nucleotide pool and RNA from isolated cytoplasmic ribosomes was investigated in the liver of female and male rats. In females, labeled orotic acid is incorporated relatively more into uridine than into cytidine nucleotides; the opposite is true for males. The administration of alpha-hexachlorocyclohexane (alpha-HCH) decreases the specific radioactivity of rRNA cytidylic acid more in males than in females. Simultaneously, the level of liver microsomal cytochrome P-450 is increased after the administration of alpha-HCH more in males than in females. After four days of treatment with alpha-HCH, the concentrations of the uridine and cytidine components of the acid-soluble pool are slightly depressed. Following repeated administration of alpha-HCH, the utilization of labeled uridine for the synthesis of cytidine nucleotides of the acid-soluble pool and RNA is depressed, whereas that of labeled cytidine is enhanced. Repeated administration of alpha-HCH decreases the utilization of [2-14C]orotic acid for the synthesis of cytidine nucleotides of DNA; the specific radioactivity of thymidylic acid is increased. The administration of beta-diethylaminoethyl diallylacetate (CFT-1201) to animals that have repeatedly received alpha-HCH decreases the specific radioactivity of DNA thymine.
在雌性和雄性大鼠肝脏中，研究了利用[2-¹⁴C]乳清酸合成游离核苷酸池中的嘧啶成分以及从分离的细胞质核糖体合成RNA的情况。在雌性大鼠中，标记的乳清酸相对更多地掺入尿苷而非胞苷核苷酸中；雄性大鼠则相反。给予α-六氯环己烷（α-HCH）后，雄性大鼠rRNA胞苷酸的比放射性降低幅度大于雌性大鼠。同时，给予α-HCH后，雄性大鼠肝脏微粒体细胞色素P-450水平的升高幅度大于雌性大鼠。用α-HCH处理四天后，酸溶性池中的尿苷和胞苷成分浓度略有降低。重复给予α-HCH后，标记尿苷用于合成酸溶性池和RNA的胞苷核苷酸的利用率降低，而标记胞苷的利用率则提高。重复给予α-HCH会降低[2-¹⁴C]乳清酸用于合成DNA胞苷核苷酸的利用率；胸苷酸的比放射性增加。给反复接受α-HCH的动物注射β-二乙氨基乙基二烯丙基乙酸酯（CFT-1201）会降低DNA胸腺嘧啶的比放射性。
