Effects of Permethrin on sexual behaviour and plasma concentrations of pituitary-gonadal hormones in adult male NMRI mice

Pyrethroids are commonly used as insecticides for both household and agricultural purposes, and recently have been shown to have detrimental effects on endocrine system. Permethrin is a type I pyrethroid which is used widely in Iran. In the present study the effects of permethrin on sexual behaviour and plasma level of PG (pituitary-gonadal) hormones of adult male mice were investigated. Mice received daily Intra peritoneal injection of permethrin (10, 15, 20 mg/kg) for 5 weeks. Using receptive females, permethrin-treated male mice exhibited reduced sexual behavior (i.e. decrease in the number of sniffing, following, mounting and mating). The concentrations of plasma testosterone, LH and FSH were measured by means of ELISA method. Serum testosterone levels were reduced significantly (p<0.05) in the experimental group versus control group, whereas FSH and LH values were not altered significantly. The results of this study indicate permethrin can have detrimental effects on plasma testosterone level and sexual behavior. In regard to considerable use of this insecticide in Iran, it’s necessary to restrain its use and extent of human contact to prevent hazards of this insecticide on human body tissues.