title: Stage-specific effects of defined mixtures of polychlorinated biphenyls on in vitro development of rabbit preimplantation embryos.
abstract: PCBs adversely affect various reproductive functions. Little is known about the embryo- toxic effects during the preimplantation period in mammals. In the present study the effects of various mixtures of highly purified PCB-congeners on embryo morphology, blastocyst formation, embryo size and cell proliferation were investigated. For 24 hr, day 3 morulae and day 4 blastocysts were cultured in the presence/absence of coplanar congeners (PCB77, PCB126, and PCB169), non-coplanar congeners (PCB28, PCB52, PCB101, PCB118, PCB138, PCB153, PCB180) or both mixtures in concentrations ranging from 0.3 ng/mL to 60 microg/mL total PCB. The main effects were (1) degeneration of all embryos at 60 microg/mL, (2) reduction of cell proliferation in day 4 embryos only by coplanar PCB; in day 3 embryos, however, by all PCB-mixtures, and (3) reduction of cell proliferation in a non-linear dose response with the strongest impairment caused by the lowest concentration. Cell proliferation was decreased by 0.3 ng/mL coplanar PCB to 50% of the level in control blastocysts. Our results show that purified PCB congeners in the range of 0.3 ng/mL to 30 microg/mL affect the development of preimplantation embryos in a stage-specific and congener-specific manner. This study provides first evidence for an embryotoxic potential of coplanar PCB congeners.
authors.affiliation: Department of Anatomy and Cell Biology, Martin Luther University Faculty of Medicine, Halle (Saale), Germany.
authors.forename: A
authors.initials: A
authors.lastname: Küchenhoff
authors.forename: R
authors.initials: R
authors.lastname: Eckard
authors.forename: K
authors.initials: K
authors.lastname: Buff
authors.forename: B
authors.initials: B
authors.lastname: Fischer
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000187:drug effects; D001824:Body Constitution; D002455:Cell Division / Q000187:drug effects; D046508:Culture Techniques; D004622:Embryo, Mammalian / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D047108:Embryonic Development / Q000187:drug effects*; D004785:Environmental Pollutants / Q000009:adverse effects* / Q000493:pharmacokinetics; D005260:Female; D011078:Polychlorinated Biphenyls / Q000009:adverse effects* / Q000493:pharmacokinetics; D011247:Pregnancy; D011817:Rabbits
chemical_list: D004785:Environmental Pollutants; D011078:Polychlorinated Biphenyls