Effects of Concurrent Exposure to Tributyltin and 1,1‐Dichloro‐2,2 bis (p‐chlorophenyl) ethylene (p,p′‐DDE) on Immature Male Wistar Rats

• Published in: Basic & clinical pharmacology & toxicology 2005-12, Vol.97 (6), p.364-368
• Main Authors: Makita, Yuji, Omura, Minoru, Tanaka, Akiyo, Kiyohara, Chikako
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Body Weight - drug effects; Dichlorodiphenyl Dichloroethylene - toxicity; Drug Antagonism; Environmental Pollutants - toxicity; Genitalia, Male - drug effects; Male; Medical sciences; Organ Size - drug effects; Pharmacology. Drug treatments; Rats; Rats, Wistar; Sexual Maturation - drug effects; Thymus Gland - drug effects; Thymus Gland - growth & development; Trialkyltin Compounds - toxicity
• ISSN: 1742-7835; 1742-7843
• DOI: 10.1111/j.1742-7843.2005.pto_199.x

: 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.