The major protocol features of the rodent uterotrophic assay have been evaluated using a range of reference chemicals. The protocol variables considered include the selection of the test species and route of chemical administration, the age of the tes...
The major protocol features of the rodent uterotrophic assay have been evaluated using a range of reference chemicals. The protocol variables considered include the selection of the test species and route of chemical administration, the age of the test animals, the maintenance diet used, and the specificity of the assay for estrogens. The rodents were ovariectomized under general anesthesia via bilateral flank incisions and randomly assigned to groups of 5 animals. This study investigated the estrogenic effects of phthalates, which are DEHP and DBP, suspected as endocrine disruptors. It is concluded that three daily subcutaneous administration of test chemicals, which are di-ethylhexyl phthalate(DEHP) and di-n-butyl phthalate(DBP), to 9 week-old rodents. The results revealed that DEHP & DBP show similar uterotrophic activity in the rat and the mouse, using subcutaneous administration. DEHP and DBP failed to affect any of these parameters, which are body weight, mammary gland, vaginal and uterus histopathology. but, DBP increased uterus weight to only one rat of 1.0 g/kg group. The results conform the need for rigorous attention to experimental design and criteria for assessing estrogenic activity.