Gestational exposure to chlorpyrifos: dose response profiles for cholinesterase and carboxylesterase activity

• DOI: 10.1093/toxsci/52.1.92
• Publication Date: 2002-07-26T18:33:32Z
• Authors: T. Lassiter
• Keywords: Oxon; Carboxylesterase; Cholinesterase; Corn oil

This study investigates the in vivo dose response profiles of target enzyme cholinesterase (ChE) and detoxifying enzymes carboxylesterase (CaE) fetal maternal compartments pregnant rats dosed with chlorpyrifos [(O,O'-diethyl O-3,5,6-trichloro-2-pyridyl) phosphorothionate], a commonly used organophosphorus insecticide. Pregnant were daily (po) corn oil (0, 3, 5, 7, or 10 mg/kg) on gestational days (GD) 14-18. Animals sacrificed 5 h after last (time maximum brain inhibition) for analysis ChE CaE activity blood, liver, brain, placenta, liver brain. The vitro sensitivity (i.e., IC50, 30 min, 26 degrees C) also was determined by assaying remaining incubation range chlorpyrifos-oxon concentrations. In exposure to mg/kg from GD14-18 caused overt toxicity, dose-related decreases more notable than Dose-related effects seen chlorpyrifos-induced inhibition activities. Gestational no placental CaE, blood CaE. activities as well however, maximally inhibited even lowest dosage chlorpyrifos. valuable predicting verifying profiles. Both findings indicated that an extremely sensitive indicator exposure.