The ΔT thermal dose concept 1: in vivo teratogenesis

Abstract This project was an initial test of the hypothesis that there would be a Δ T thermal dose relationship for birth defects in rats ( Rattus norvegicus ) during neural tube closure (NTC). Additionally, the same thermal dose as applied during NTC in utero in vivo, was also applied to exteriorized (i.e., ex vivo) in utero pregnant uterine horns at a comparable stage of organogenesis. Since the yields of the two regimens were comparable, the hyperthermia-induced teratogenic effects appear to result from the thermal dosing of the in utero embryos and not the elevated temperature of the mother. The hypothesis was supported.