title: Effects of di(2-ethylhexyl) phthalate on gap and tight junction protein expression in the testis of prepubertal rats.
abstract: The aim of this study was to analyze whether di(2-ethylhexyl) phthalate (DEHP), a Sertoli and Leydig cell toxicant, is able to induce alterations in the expression of testicular gap and tight junction proteins. DEHP was administered by gavage (1 g/5 mL corn oil/kg body weight/day) to 25-day-old male Sprague-Dawley rats for 2 days (DEHP-27d) and control rats were treated with corn-oil vehicle for 2 days (C-27d); animals were killed 24 h after the last treatment. Testes of DEHP-27d rats showed different degrees of germ cell sloughing of seminiferous tubules (ST). No alterations of the blood testis barrier (BTB) by lanthanum tracer study were observed. ST of DEHP-27d rats showed a milder immunofluorescence and more restricted expression of connexin-43 (Cx43) in the adluminal and basal compartment compared to C-27d. In DEHP-27d rats, we found a discontinuous immunofluorescent (IF) pattern for zonula occludens (ZO-1), contrasting with the continuous IF profile observed in C-27d, and a delocalization of claudin-11. A decrease in Cx43 and ZO-1 and no changes in occludin expression were detected by Western blot in the testes of DEHP-27d rats. Results from 57-day-old rats treated with DEHP for 2 days and held for 30 days without treatment showed that the alterations in protein expression induced by DEHP are reversible. However, a delay of spermatogenesis compared to C-57d rats, occurred. Data demonstrated that DEHP does not impair BTB permeability but induces germ cell sloughing that might respond to a down regulation of Cx43 and ZO-1 that alters cell junction proteins.
authors.affiliation: Instituto de Investigaciones en Reproducción, Facultad de Medicina Universidad de Buenos Aires, Paraguay 2155 P10, C 1121 ABG, Buenos Aires, Argentina. ciruba@fmed.uba.ar
authors.forename: Cristian M
authors.initials: CM
authors.lastname: Sobarzo
authors.forename: Livia
authors.initials: L
authors.lastname: Lustig
authors.forename: Roberto
authors.initials: R
authors.lastname: Ponzio
authors.forename: María Olga
authors.initials: MO
authors.lastname: Suescun
authors.forename: Berta
authors.initials: B
authors.lastname: Denduchis
mesh_terms: D000818:Animals; D017630:Connexins / Q000096:biosynthesis*; D004051:Diethylhexyl Phthalate / Q000633:toxicity*; D017629:Gap Junctions / Q000187:drug effects*; D007985:Leydig Cells / Q000187:drug effects; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012671:Seminiferous Tubules / Q000187:drug effects*; D012708:Sertoli Cells / Q000187:drug effects; D013737:Testis / Q000187:drug effects*; D019108:Tight Junctions / Q000187:drug effects*
chemical_list: D017630:Connexins; D004051:Diethylhexyl Phthalate