title: Effects of concurrent exposure to tributyltin and 1,1-dichloro-2,2 bis (p-chlorophenyl) ethylene (p,p'-DDE) on immature male Wistar rats.
abstract: Tributyltin and 1, 1-dichloro-2, 2 bis (p-chlorophenyl) ethylene (p,p'-DDE) have been ubiquitously distributed over the world. In Japan, p,p'-DDE and tributyltin are ingested through marine products, in which these substances are accumulated through bio-concentration and the food chain. However, the consequence of potential combined hazards of these substances remains unknown. Therefore, the effects of concurrent exposure to 125 ppm p,p'-DDE and 25 ppm tributyltin were investigated in immature male Wistar rats by oral administration during puberty. In this study, tributyltin promoted the growth of pubertal male rats, while p,p'-DDE itself did not affect the growth but inhibited the growth enhancement by tributyltin. Furthermore, tributyltin reduced thymus weight but p,p'-DDE also prevented this weight reduction. Neither development of male sexual accessory organs nor sexual maturation was affected even by concurrent exposure to p,p'-DDE and tributyltin. No significant changes of serum testosterone, luteinizing hormone, follicle-stimulating hormone concentrations, and epididymal sperm numbers were observed with the administration of p,p'-DDE and/or tributyltin. These results indicate that sexual maturation, male reproductive organ development and sperm production is scarcely affected in immature male Wistar rats even by concurrent exposure to p,p'-DDE and tributyltin at a daily dose of ca. 2 mg/kg tributyltin and 10 mg/kg p,p'-DDE. Moreover, the simultaneous administration of p,p'-DDE with tributyltin counterbalanced the effects that were attributed to tributyltin alone.
authors.affiliation: Department of Hygiene, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan. ymakita@eisei.med.kyushu-u.ac.jp
authors.forename: Yuji
authors.initials: Y
authors.lastname: Makita
authors.forename: Minoru
authors.initials: M
authors.lastname: Omura
authors.forename: Akiyo
authors.initials: A
authors.lastname: Tanaka
authors.forename: Chikako
authors.initials: C
authors.lastname: Kiyohara
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D003633:Dichlorodiphenyl Dichloroethylene / Q000633:toxicity*; D004336:Drug Antagonism; D004785:Environmental Pollutants / Q000633:toxicity*; D005837:Genitalia, Male / Q000187:drug effects; D008297:Male; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D012741:Sexual Maturation / Q000187:drug effects; D013950:Thymus Gland / Q000187:drug effects / Q000254:growth & development; D014220:Trialkyltin Compounds / Q000633:toxicity*
chemical_list: D004785:Environmental Pollutants; D014220:Trialkyltin Compounds; D003633:Dichlorodiphenyl Dichloroethylene; C011559:tributyltin