Content of Glutathione and Vitamin C in the Liver of Rats Exposed to Dimethoate and Pyrantel Tartrate

Spodniewska A. , A. Zasadowski: Content of Glutathione and Vitamin C in the Liver of Rats Exposed to Dimethoate and Pyrantel Tartrate. Acta Vet. Brno 2008, 77: 355-362. The study was undertaken to examine the effect of oral administration of dimethoate (Bi 58 Nowy) and/or pyrantel tartrate on the concentration of glutathione (GSH) and vitamin C in rat liver. Rats of Group I were administered pyrantel tartrate at a dose of 85 mg/kg b.w. at a twoweek interval, while the animals of Group II received Bi 58 Nowy (38% dimethoate) at a dose of 25 mg/kg b.w. for 28 days, and animals of Group III received both compounds together as described above. Pyrantel tartrate was found to increase the concentration of glutathione in the liver, whereas the content of vitamin C oscillated around values reported for the control. After a 28-day exposure to dimethoate (Bi 58 Nowy), except for the 6th hour after intoxication, the content of GSH was observed to increase and significant differences (p ≤ 0.05) occurred after days 3 and 14 (p ≤ 0.01). The concentration of vitamin C in liver homogenates after dimethoate administration was decreased compared to the control until day 3. An increase was then observed continuing until the end of the experiment. In animals receiving both compounds, except for day 7, the concentration of vitamin C was slightly decreased. The administration of pyrantel tartrate before dimethoate (Bi 58 Nowy) only in some time intervals was found to reduce the intensity of changes evoked by the exclusive administration of insecticide. It may suggest that not in all cases of mixed intoxications, intensification should be expected in changes of the variables analyzed. Dimethoate, pyrantel tartrate, glutathione, vitamin C, rat Amongst the threats posed by chemical substances, special attention should be paid to hazards linked to the use of pesticides (Jeyaratnam 1990; Steenland et al. 1994, 1996). Due to their extensive use, the problem of their toxic interactions with various compounds, including drugs, becomes of key importance in terms of both biological and therapeutic effects observed as well as mechanisms affecting this phenomenon. Organophosphate (OP) insecticides, including dimethoate (O,O-dimethyl S-methylcarbamoylmethyl phosphorodithioate), due to their rapid degradation in the environment, are one of the major and most extensively used pesticides in agriculture (Pruett 1996; LUIS 1997). The mechanism of the toxic action of dimethoate (similar to other OP compounds) is one of inhibiting the acetylcholinesterase activity. Recent studies have also demonstrated that organophosphate insecticides induce oxidative stress through generation of free radicals and induction of lipid peroxidation (Altuntas et al. 2003; Abdollahi et al. 2004; Yarsan and Cakir 2006). Pyrantel tartrate (trans-1, 4, 5, 6-tetrahydro-1-methyl-2-[2-(thienyl)-vinyl] pyrimidine) is a commonly used, effective agent against intestinal nematodes in horses and pigs (Valdez et al. 1995; Lyons et al. 2007). It exhibits a strong agonistic effect on nicotine receptors (AChRs) and capacity for blocking open ion channels linked with AChRs (Rayes et al. 2001). Due to the significant role of oxidative stress in the toxic action of pesticides and other chemical compounds (including drugs) (Yarsan et al. 1999; Altuntas et al. 2004; Address for correspondence: Anna Spodniewska Division of Veterinary and Environmental Toxicology Department of Pathology and Pharmacology, Faculty of Veterinary Medicine University of Warmia and Mazury in Olsztyn Oczapowskiego 14, 10-719 Olsztyn, Poland E-mail: anspod@uwm.edu. pl http://www.vfu. cz/acta-vet/actavet.htm ACTA VET. BRNO 2008, 77: 355–362; doi:10.2754/avb200877030355