Histological alterations in ovaries of pubertal female rats induced by triphenyltin

Triphenyltin is an organotin compound that has been used extensively as an antifouling biocide and as an agricultural pesticide. Certain organotin compounds act as endocrine-active agents and have been reported to affect reproduction in mollusks and mammals. Here we studied the histopathological effects of 2 or 6 mg triphenyltin chloride (TPTCl)/kg b.w. on the reproductive tissue and the thymus of female pubertal rats as part of a comprehensive pubertal assay. Beginning at postnatal day (PND) 23 female Wistar rats were treated daily per gavage until their first estrus after PND 53. Reproductive organs were removed and histologically evaluated. While no histological changes were observed in oviduct, uterus, vagina and mamma, an increase in the number of all follicle stages occurred at both dose levels. Furthermore, exposure to 2 mg TPTCl/kg b.w. led to a significant reduction in the diameter of tertiary follicles. A significant increase in the number of atretic follicles was observed in tertiary and preovulatory follicles after exposure to 6 mg TPTCl. The thymus displayed a decreased number of apoptotic cells in both dose groups. We conclude that peripubertal administration of 2 and 6 mg TPTCl/kg b.w. caused effects on ovarian follicles of female rats.