Spontaneous Mammary Cancer Developing in Rats Born and Nursed by Mothers Treated with 3-Methylcholanthrene.

Publisher Website
Google Scholar
Abstract
Four female rats among a total of 28 (7 males and 21 females) surviving offspring of mothers treated with 3-methylcholanthrene before pregnancy developed spontaneous mammary cancers at the age of 49, 85, 90 and 90 days. Spontaneous mammary cancer was also observed in 1 female rat among a total of 12 (3 males and 9 females) offspring of mothers treated with 3-methylcholanthrene during pregnancy. Spontaneous mammary carcinomas in rats have never been reported to appear at an age earlier than 300 days. The mechanism by which these tumors develop is of considerable interest. Present data indicate that 3-methylcholanthrene is able to pass the placental barrier.