| Title : The effect of 2-(o-cresyl)-4H-1:3:2-benzodioxaphosphorin-2-oxide on tissue cholinesterase and carboxylesterase activities of the rat - Jimmerson_1989_Fundam.Appl.Toxicol_13_568 |
| Author(s) : Jimmerson VR , Shih TM , Maxwell DM , Kaminskis A , Mailman RB |
| Ref : Fundamental & Applied Toxicology , 13 :568 , 1989 |
| Abstract : The dose-response (0.1 to 1000 mg/kg sc) effects of 2-(o-cresyl)-4H-1:3:2-benzodioxaphosphorin-2-oxide (CBDP; a metabolite of the organophosphorus compound tri-o-cresylphosphate) on total cholinesterase (ChE) and carboxylesterase (CaE) activities in tissues from the rat were examined. Doses of CBDP greater than 1.0 mg/kg inhibited CaE activity maximally (greater than 99%) in plasma and lung, two important sites for detoxification of organophosphorus toxicants. A biphasic dose-dependent inhibition of ChE activity was seen in all tissues; the ED50 values showed a difference of two orders of magnitude between the first and the second phases of the dose-response curves. CBDP inhibited the blood esterases in the order plasma CaE much greater than plasma ChE much greater than red blood cell (RBC) ChE. The biphasic dose-response curve and preferential inhibition of the blood esterases may reflect the inhibition of butyrylcholinesterase in preference to acetylcholinesterase in these tissues. At doses of CBDP below 1.0 mg/kg, plasma, RBC, and brain regional ChE activities were inhibited by less than 10%, whereas at doses above 2.0 mg/kg, ChE activities were inhibited substantially (up to 80% in plasma, up to 60% in RBC, and greater than 90% in brain regions). On the basis of these results, a dose of CBDP between 1.0 and 2.0 mg/kg should prove useful as a pretreatment for studies of OP toxicity in the rat. |
| ESTHER : Jimmerson_1989_Fundam.Appl.Toxicol_13_568 |
| PubMedSearch : Jimmerson_1989_Fundam.Appl.Toxicol_13_568 |
| PubMedID: 2612789 |
Jimmerson VR, Shih TM, Maxwell DM, Kaminskis A, Mailman RB (1989)
The effect of 2-(o-cresyl)-4H-1:3:2-benzodioxaphosphorin-2-oxide on tissue cholinesterase and carboxylesterase activities of the rat
Fundamental & Applied Toxicology
13 :568
Jimmerson VR, Shih TM, Maxwell DM, Kaminskis A, Mailman RB (1989)
Fundamental & Applied Toxicology
13 :568