title: Dose-response relationships of retinol in production of the Arnold-Chiari malformation.
abstract: A single oral dose of 5000, 10 000, 15 000, 20 000 or 30 000 I.U. vitamin A alcohol (retinol) on the eighth day of gestation in the pregnant hamster resulted in the production of the Arnold-Chiari malformation types I and II in 0, 6.6, 57, 56 and 85%, respectively, of all fetuses examined. The pattern and severity of the malformations of the chondrocranium and viscerocranium changed as the dose of retinol was increased. The smallest dose of retinol used in the present study which induced gross terata in hamsters was approximately 11 times greater than the highest oral daily dose of retinol used in clinical cancer chemoprevention trials.
mesh_terms: D000014:Abnormalities, Drug-Induced / Q000209:etiology*; D000818:Animals; D001139:Arnold-Chiari Malformation / Q000139:chemically induced*; D006224:Cricetinae; D004305:Dose-Response Relationship, Drug; D005260:Female; D011247:Pregnancy; D014801:Vitamin A / Q000633:toxicity*
chemical_list: D014801:Vitamin A