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Increase in lactate dehydrogenase isoenzyme-4 and splenocyte toxicity in methomyl-treated rats
1Faculty of Pharmaceutical Sciences, Naresuan University, Pitsanulok, Thailand.
Abstract:
The toxic effect of methomyl was studied in rats after a single or repeated oral administration. Rats treated with a single dose of methomyl (3, 5, or 7 mg/kg) showed significant increase (P < 0.05) in total lactate dehydrogenase (LDH) activity on day 1. The highest level of LDH activity was observed on day 3 in rats receiving 7 mg/kg of methomyl. The total LDH activity returned to normal on day 7 after dosing. Specific increases in LDH-3 and LDH-4 isoenzyme activities were observed. In rats treated with a single dose of 6 and 8 mg/kg of methomyl, spleen weight and splenocyte viability significantly dropped (P < 0.05) on days 1 and 3, respectively. Splenotoxicity was prevented by pretreatment with 60 mg/kg of N-acetylcysteine. The results suggest that the splenotoxic effect of methomyl is more likely directly related to oxidative cell injury than to cholinesterase inhibition. The significance of cytotoxic effects and the nature of cytotoxicity in relation to reactive oxidative damage deserve further investigation.
Insights
Methomyl exposure in rats increased lactate dehydrogenase (LDH) levels and caused spleen damage. N-acetylcysteine protected against methomyl
Area of Science:
- Toxicology
- Biochemistry
Background:
- Methomyl is a carbamate insecticide.
- Understanding its toxicological effects is crucial for risk assessment.
Purpose of the Study:
- To investigate the toxic effects of methomyl in rats.
- To explore the mechanism of methomyl-induced splenotoxicity.
Main Methods:
- Rats received single oral doses of methomyl.
- Lactate dehydrogenase (LDH) activity and isoenzymes were measured.
- Spleen weight and splenocyte viability were assessed.
- The effect of N-acetylcysteine was evaluated.
Main Results:
- Methomyl administration increased total LDH activity and specific isoenzymes (LDH-3, LDH-4).
- Significant reductions in spleen weight and splenocyte viability were observed.
- N-acetylcysteine pretreatment prevented methomyl-induced splenotoxicity.
Conclusions:
- Methomyl exhibits dose-dependent toxicity affecting LDH levels and spleen health.
- Splenotoxicity appears to be mediated by oxidative stress rather than cholinesterase inhibition.
- Further research is needed to elucidate the cytotoxic mechanisms and oxidative damage.
