title: Toxic effects of cypermethrin on the male reproductive system: with emphasis on the androgen receptor.
abstract: The 15-day intact adult male assay was used to investigate the reproductive toxicity of cypermethrin. We also evaluated the contributions of the androgen receptor (AR) to cypermethrin-induced reproductive impairments. Sixty adult male Sprague-Dawley rats were randomly divided into five groups and treated with different doses of cypermethrin (0, 6.25, 12.5, 25 and 50 mg kg(-1) per day) by oral gavage for 15 days. After the rats were sacrificed, the testes, epididymides, seminal vesicles and prostates were excised and weighed. One testis was frozen to be used for daily sperm production. Another testis was processed for AR immunohistochemical analysis and electron microscopic observation. We found that the weights of prostates were significantly decreased in cypermethrin treatment at doses of 25 and 50 mg kg(-1) per day. Rats treated with cypermethrin at 50 mg kg(-1) per day exhibited a significant reduction in testicular daily sperm production. Seminiferous tubule changes were noted, including atrophy and distorted seminiferous tubules, reduction and deformation of spermatogonia, spermatocyte and disordered arrangement of spermatoblasts. Ultrastructural changes were found in cypermethrin-treated groups with disrupted cellular junctions, abnormal morphology of the nucleus, necrosis of spermatogonia spermatocytes and Sertoli cells. To clarify the possible mechanism, AR expression and the serum levels of testosterone were assayed. AR levels were significantly reduced in the rats treated with cypermethrin and the serum levels of testosterone were reduced in cypermethrin treatment at a dose of 50 mg kg(-1) per day. These data suggested that cypermethrin can induce impairments of the structure of seminiferous tubules and spermatogenesis in the male rats. The impairments can be attributed to the reduced AR expression.
authors.affiliation: The School of Public Health, Xuzhou Medical College, 84 West Huai-hai Road, Xuzhou, Jiangsu, 221002, China.
authors.forename: Jin-xia
authors.initials: JX
authors.lastname: Hu
authors.forename: Yan-fang
authors.initials: YF
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Chen
authors.initials: C
authors.lastname: Pan
authors.forename: Zhen
authors.initials: Z
authors.lastname: He
authors.forename: Hong-yan
authors.initials: HY
authors.lastname: Dong
authors.forename: Li-chun
authors.initials: LC
authors.lastname: Xu
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005640:Follicle Stimulating Hormone / Q000097:blood; D005837:Genitalia, Male / Q000187:drug effects*; D007150:Immunohistochemistry; D007306:Insecticides / Q000378:metabolism / Q000633:toxicity*; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D008854:Microscopy, Electron; D009929:Organ Size / Q000187:drug effects; D011722:Pyrethrins / Q000378:metabolism / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011944:Receptors, Androgen / Q000187:drug effects*; D012671:Seminiferous Tubules / Q000187:drug effects / Q000473:pathology / Q000648:ultrastructure; D013076:Sperm Count; D013090:Spermatocytes / Q000187:drug effects / Q000648:ultrastructure; D013091:Spermatogenesis / Q000187:drug effects; D013093:Spermatogonia / Q000187:drug effects / Q000648:ultrastructure; D013737:Testis / Q000473:pathology / Q000648:ultrastructure
chemical_list: D007306:Insecticides; D011722:Pyrethrins; D011944:Receptors, Androgen; C017160:cypermethrin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone