A teratologic evaluation of continuous-wave, daily ultrasound exposure in unanesthetized pregnant rats

摘要: Pregnant Sprague-Dawley rats were trained to remain immobile when placed in water an ultrasound exposure tank and exposed 0, 0.1, 2.0, or 30.0 W/cm2 ISPTA (spatial peak, temporal average), 3.0-MHz continuous wave (cw) on embryonic (E) days 4-19 for approximately 15 min/day. On E20 fetuses removed; weighed; examined external, skeletal, visceral malformations; uteri resorptions. Analyses revealed no increase pre-implantation loss effects maternal body weight, food, consumption. No skeletal malformations was found, fact groups had a lower incidence of defects than controls. A significant resorptions the lowest group (0.1 W/cm2) obtained, but effect isolated, non-dose dependent not credible as treatment-related effect. reduction fetal weight (0.1-W/cm2) middle (2.0-W/cm2) level weighed slightly more The immobility procedure succeeded avoiding anesthetization forced restraint dams, thereby eliminating these factors potential confounders. results demonstrated that unanesthetized, unrestrained utero incident intensities up cw (or estimated internal exposures 4-21 W/cm2, depending orientation beam) produced evidence embryotoxicity based necropsy data.