TY - JOUR A1 - , T1 - Histological examination of major craniofacial abnormalities produced in rat foetuses with a variety of retinoids JO - Eur. J. Anat. SN - 1136-4890 Y1 - 2007 VL - 11 SP - 17 EP - 26 UR - http://www.eurjanat.com/web/paper.php?id=07010017 KW - retinoic acid derivative KW - retinoid derivative KW - retinol KW - animal experiment KW - animal model KW - animal tissue KW - article KW - cleft lip palate KW - controlled study KW - craniofacial malformation KW - embryo KW - exencephaly KW - exophthalmos KW - female KW - fetotoxicity KW - fetus KW - gestational age KW - histology KW - histopathology KW - nonhuman KW - pregnancy KW - rat KW - teratogenicity KW - teratoma KW - Wistar rat N2 - Retinoic acid is a vitamin-A derived compound that plays an important role in craniofacial development. However, numerous studies have shown that exogenously administered retinoic acid analogues have teratogenic effects both in humans and in experimental animals. This paper presents the results of a study where exogenous administration of retinoic acid analogues to pregnant Wistar rats resulted in major craniofacial malformations of most of the foetuses. Seven groups of pregnant rats were exposed to a variety of retinoic acid analogues, administered in different doses on different gestational days. A further control group was not exposed to these compounds. All the rats were impregnated and sacrificed on the same gestational days (GD 0 and GD 18 respectively). Following examination of the 34 foetuses obtained from the retinoic acid-treated litters, 5 were chosen for histological investigation to describe the major, external craniofacial malformations resulting from exposure to the teratogens. These malformations included exophthalmos, anophthalmos, exencephaly, craniofacial asymmetry and facial tags. Also reported here are the incidences of teratomas and absorptions in these litters. Previously, we have reported the incidence of cleft lip and palate in rats subjected to an identical experimental regimen. Our data provide further evidence that retinoic acid analogues, all-trans-retinoic acid in particular, disturb normal craniofacial development in such a way that a spectrum of craniofacial malformations can be induced by embryonic exposure to these compounds. ER -