Kolb E
Veterinär-Physiologisch-Chemisches Institut, Universität Leipzig.
Berl Munch Tierarztl Wochenschr. 1994 Oct;107(10):342-7.
Cases of hypervitaminosis A in men--especially in pregnant women, with development of malformations--are reported. The existence of withdrawal times to slaughter after the application of vitamin-A-containing preparations with a content of 10,000 to 10(6) international units and more is described. The content of vitamin A in the liver of monogastric animals is closely related to that in the feed. In ruminants about 40 to 70% of the vitamin A of the feed is decomposed by the microorganisms in the forestomachs. The amount of vitamin A stored in the liver after a therapeutic application is dependent of the initial content. The velocity of the depletion of the stores at a carotene- and vitamin-A-poor feeding is described. In ruminants and pigs in the account of the properties of the placenta no embryotoxicity of a therapeutic dose of vitamin A is to be expected. The mechanism of the teratogenesis by vitamin A in mice is described.
有报告称男性出现维生素A过多症病例——尤其是孕妇，伴有畸形发育。文中描述了在使用含10,000至10⁶国际单位及以上维生素A制剂后到屠宰的停药期。单胃动物肝脏中维生素A的含量与饲料中的含量密切相关。在反刍动物中，饲料中约40%至70%的维生素A被前胃中的微生物分解。治疗性应用后肝脏中储存的维生素A量取决于初始含量。文中描述了在低胡萝卜素和维生素A饲料喂养下储存量的消耗速度。由于胎盘的特性，反刍动物和猪中治疗剂量的维生素A预计无胚胎毒性。文中描述了维生素A在小鼠中致畸的机制。
