The Indirect Effect of Irradiation on Embryonic Development

Abstract

IntroductionMany factors contribute to the production of congenital malformations. It is the job of the experimentalist to decide what is their relative importance and to uncover all the contributing factors and their interrelationships.This same philosophy applies to congenital malformations caused by one etiology, namely, irradiation. The factors responsible for radiation teratogenesis are multiple and interrelated. Any classification would be completely arbitrary. For the purposes of this paper, the role of radiation can be thought of as mediated directly through the embryo, and indirectly through irradiation of the placenta and/or mother. It is the purpose of this and the subsequent paper to decide on how important these so-

Bob Brent: Scientist, physician, scholar, teacher, mentor, and mensch

“…Additional studies with McLaughlin and Bolden clarified that even radiation doses as high as 4 Gy to the head, chest and extremities had little adverse effect on the developing embryo. In order to induce malformations, the embryo had to be directly exposed to radiation at doses >0.20 Gy (Brent, 1960(Brent, , 1969Brent & Bolden, 1967a, 1967b, 1968Brent & Mclaughlin, 1960).…”

Indirect Effect of Irradiation on Embryonic Development. IV. Lethal Effects of Maternal Irradiation on First Day of Gestation In the Rat.

“…The concept of a maternal or indirect effect of irradiation to the zygote or embryo has interested several investigatojrs (1)(2)(3)(4)(5)(6)(7). There is still some disagreement among authors as to whether a "maternal" effect exists.…”