Abstract
Compared to popular subjects on teratogenesis due to radiation, such as microcephaly/central nervous system malformation, little has been reported on the congenital cardiovascular anomalies following maternal exposures. To collect data on prevention and treatment of congenital teratogenesis, examination of the effects of exposure to various types of radiation and teratogenesis is necessary. We focus on embryonic lethality, external malformations, and visceral malformations of cardiovascular origin caused by maternal exposure to varying dosage of radiations, such as 60Co gamma ray and neutron irradiation. We observed a high frequency of teratogenesis, especially cardiovascular and craniofacial anomalies, in the irradiated groups differing by the day of maternal exposure. These results indicate the high radiation sensitivity of rat fetuses to neurocristopathy syndromes, especially double outlet right ventricle, riding aorta, Tetralogy of Fallot, transposition of the great arteries, aortic arch anomalies, and lung/trachea anomalies. In humans, these conditions are termed Alagille Syndrome and DiGeorge-Velocardiofacial Syndromes, and this animal model is expected to contribute in the human investigation of such teratogenesis as well. Although progress has been made in identifying the mechanism of birth defects on the molecular level, many pieces to the puzzle still remain missing. In future studies of teratogenesis due to radiation, any approach will require not only the observation of human fetal specimen, but also the use of solid animal experiment models.
