DYSMORPHOGENIC EFFECTS OF IVOMEC IN MOUSE EMBRYOS IN VITRO

Iverm ectin is an antiparasitic agent used in animals and humans and is often administered as a 1% solution (Ivomec, Merck) dissolved in propylene glycol and glycerol formal. Ivermectin alone produces minor adverse reactions in humans and farm animals, but mice are particularly sensitive to the drug, demonstrating neurotoxicity in adults and malformations in offspring at relatively low maternal doses. Ivom ec and its constituent solvents, propylene glycol and glycerol formal, have not been previously examined for their direct effect on embryonic development. In this study the in vitro method of whole-embryo culture was used to expose early-som ite mouse embryos to Ivomec, propylene glycol, and glycerol formal. Pure iverm ectin could not be obtained from the manufacturer and thus could not be evaluated individually. Ivomec was added to the culture medium to achieve ivermectin concentrations of 0, 5, 10, 25, and 50 ug/ ml. Controls for each group were exposed to propylene glycol and glycerol formal (no iver...