Induction of hepatic microsomal cytochrome P-450 and inhibition of brain, liver, and plasma esterases by an acute dose of S,S,S-tri-n-butyl phosphorotrithioate (DEF) in the adult hen.
Lapadula DM; Carrington CD; Abou-Donia MB
Toxicol Appl Pharmacol 1984 Apr; 73(2):300-310
The effects of oral and dermal administration of S,S,S-tri-n-butyl- phosphorotrithioate (150505) (DEF) on specific enzymes in the nervous system and plasma were investigated in leghorn-hens. Hens were administered 100, 200, 500, or 1000mg/kg DEF dermally or orally; 24 hours later, hens were decapitated. To determine the effects of microsomal enzyme inducers, hens were treated with sodium- phenobarbital or 3-methylcholanthrene daily for 3 days, or were administered a single dermal dose of 1000mg/kg DEF. Hens administered dermal doses or large oral doses of 500 and 1000mg/kg DEF or parathion (negative control) exhibited signs of acute cholinergic toxicity within 24 hours of dosing. Hens treated with 500mg/kg tri-o-cresyl-phosphate (TOCP) as a positive control did not show acute poisoning signs. The findings demonstrate that inhibition of the three nonspecific esterases is associated with the DEF dose and the dermal route of entry that produces organophosphorus induced delayed neurotoxicity (OPIDN). Parathion and orally administered DEF did not cause OPIDN and did not inhibit these esterases to the same extent as did TOCP and dermally applied DEF, both of which are capable of producing OPIDN.
NIOSH-Publication; NIOSH-Grant; Neurotoxic-effects; Laboratory-animals; Herbicides; Agricultural-chemicals; Nervous-system-disorders; Neuropathology; Neurotoxic-effects; Organo-phosphorus-compounds; Enzyme-activity
Pharmacology Duke University Department of Pharmacology Durham, N C 27710
Neurotoxic Disorders; Neurotoxic-effects
Toxicology and Applied Pharmacology
Duke University, Durham, North Carolina