title: Tributyltin impairs the reproductive cycle in female rats.
abstract: Triorganotins are environmental contaminants, commonly used in antifouling agents for boats, that bioaccumulate and thus are found in mammals and humans due to ingestion of contaminated seafood diets. The importance of triorganotins as environmental endocrine disruptors and consequent reproductive toxicity in different animal models is well known; however, the adverse effects on reproductive cycle are less well understood. The potential reproductive toxicity of tributyltin (TBT) on regular reproductive cycling of female rats was examined. Wistar female rats (12 wk old, weighing approximately 230 g) were divided into two groups: control (vehicle, ethanol 0.4%) and tributyltin (100 ng/kg/d, 7 d/wk, for 16 d by gavage). Tributyltin significantly decreased the cycle regularity (%), duration of the reproductive cycle, the proestrus and diestrus phases, and number of epithelial cell in proestrus phase. TBT also increased the duration of metestrus and the number of cornified cells in this phase. Ovary weight and serum 17β-estradiol levels decreased markedly, accompanied by a significant increase in progesterone levels. Histological analysis showed apoptotic cells in corpus luteum and granulosa cells layer, with cystic follicles after TBT exposure. Tributyltin also elevated number of atretic follicles and corpoa lutea. The micronucleus (MN) test, using Chinese hamster ovary cells, demonstrated a concentration-dependent mutagenic effect of TBT, and at 2.0 × 10(-2)ng/ml most of the cells were nonviable. The toxic potential of TBT over the reproductive cycle may be attributed to changes found in the ovarian weight, unbalanced levels of sexual female hormones, and number of ovarian follicles and corpora lutea.
authors.affiliation: Department of Morphology, Federal University of Espirito Santo-UFES, Espírito Santo, Brazil.
authors.forename: Priscila
authors.initials: P
authors.lastname: Lang Podratz
authors.forename: Vicente Sathler
authors.initials: VS
authors.lastname: Delgado Filho
authors.forename: Pedro Francisco Iguatemy
authors.initials: PF
authors.lastname: Lopes
authors.forename: Gabriela
authors.initials: G
authors.lastname: Cavati Sena
authors.forename: Silvia Tamie
authors.initials: ST
authors.lastname: Matsumoto
authors.forename: Vivian Yochiko
authors.initials: VY
authors.lastname: Samoto
authors.forename: Christina Maeda
authors.initials: CM
authors.lastname: Takiya
authors.forename: Emilio
authors.initials: E
authors.lastname: de Castro Miguel
authors.forename: Ian Victor
authors.initials: IV
authors.lastname: Silva
authors.forename: Jones Bernardes
authors.initials: JB
authors.lastname: Graceli
mesh_terms: D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D030762:Estrous Cycle / Q000187:drug effects*; D005260:Female; D009929:Organ Size / Q000187:drug effects; D010053:Ovary / Q000187:drug effects / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D014220:Trialkyltin Compounds / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014220:Trialkyltin Compounds; D014874:Water Pollutants, Chemical; C011559:tributyltin