title: Effect of subchronic exposure to malathion on glycogen phosphorylase and hexokinase activities in rat liver using native PAGE.
abstract: The aim of this study was the evaluation of the effects of a subchronic exposure to malathion, an organophosphorus (OP) insecticide, on plasma glucose and hepatic enzymes of glycogenolysis and glycolysis in rats in vivo. Malathion was administered intragastrically by stomach tube in the amount of 1 ml corn oil containing 100mg/kg body weight (BW) daily for 32 days. At the end of the experiment, the liver was removed. The activities of glycogen phosphorylase (GP) and hexokinase (HK) were analysed in the homogenate. The methodology employed was a non-denaturing electrophoresis followed by activity-staining (native PAGE). Malathion decrease GP activity by 50% and increase HK activity by 10%. In addition, an hepatomegaly was recorded with a rise in the hepatic glycogen rate in malathion-treated rats. Moreover, subchronic administration of malathion has no effect on blood glucose concentration. The storage of glycogen in liver may be due to a stimulation of insulin secretion after the inhibition of acethylcholinesterase activity in pancreatic beta cells by malathion. These findings were in favour of an activation of glycogen storage by malathion.
authors.affiliation: Laboratoire de Physiologie des Agressions, Faculté des Sciences de Tunis, Tunis, Tunisia.
authors.forename: Raja
authors.initials: R
authors.lastname: Rezg
authors.forename: Bessem
authors.initials: B
authors.lastname: Mornagui
authors.forename: Mosbeh
authors.initials: M
authors.lastname: El-Arbi
authors.forename: Abdelaziz
authors.initials: A
authors.lastname: Kamoun
authors.forename: Saloua
authors.initials: S
authors.lastname: El-Fazaa
authors.forename: Najoua
authors.initials: N
authors.lastname: Gharbi
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D004591:Electrophoresis, Polyacrylamide Gel; D006003:Glycogen / Q000378:metabolism*; D024981:Glycogen Phosphorylase / Q000378:metabolism*; D006593:Hexokinase / Q000378:metabolism*; D007306:Insecticides / Q000633:toxicity*; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D008294:Malathion / Q000633:toxicity*; D008297:Male; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar
chemical_list: D001786:Blood Glucose; D007306:Insecticides; D006003:Glycogen; D024981:Glycogen Phosphorylase; D006593:Hexokinase; D008294:Malathion