In utero exposure to tributyltin alters the expression of e-cadherin and localization of claudin-1 in intercellular junctions of the rat ventral prostate

Tributyltin (TBT) is an environ- mental contaminant, exhibiting well-established toxi- city to reproductive systems in aquatic organisms. Little information exists regarding the effects of TBT on mammalian reproduction. Cellular junctions are crucial for sperm development and maturation. Intercellular tight junctions are formed by transmembrane proteins such as claudins (Cldns), while the formation of tight junctions involves signaling components of adhering junctions, comprised of cadherins. The objectives of this study were to determine the effects of in utero exposure to TBT on the rat ventral prostate. Pregnant Sprague-Dawley rats were given doses of TBT (2.5, 10, or 20 mg/kg) throughout gestation and sacrificed at Day 91. Ventral prostate weights of TBT-treated rats were decreased in all treatment groups. Results of gene expression macro-array analysis indicated that numer- ous genes related to cellular adhesion and cell polarity were affected. Cldn-1 mRNA levels decreased after exposure to TBT. Cldn-1 was immunolocalized to the apical lateral margins of adjacent prostatic epithelial cells in controls, but was increasingly dispersed along the lateral plasma membrane with increasing TBT dose, suggesting that the targeting of Cldn-1 or its localization to tight junctions was altered as a result of fetal TBT exposure. E-cadherin mRNA levels and immunolocalization were decreased in a dose-depen- dent manner. These data indicate that in utero TBT exposure results in permanent alterations in ventral prostate and that these are associated with alterations in the expression and distribution of cell adhesion and tight junctional proteins. Mol. Reprod. Dev. 74: 455-467, 2007. 2006 Wiley-Liss, Inc.