@phdthesis{Fritzsche2005,
  author    = {Fritzsche, Britta},
  title     = {Einfluss Retins{\"a}ure-metabolisierender Enzyme auf die Implanttion und die fr{\"u}he Gestation in den Modelltieren Maus und Ratte},
  pages     = {vii, 130 S. : graph. Darst.},
  year      = {2005},
  language  = {de}
}
@article{FritzscheSchuchardtSchmidtetal.2010,
  author    = {Fritzsche, Britta and Schuchardt, Jan-Philipp and Schmidt, Anja and Nau, Heinz and Schweigert, Florian J. and Ruehl, Ralph},
  title     = {CYP26A1-specific antagonist influence on embryonic implantation, gene expression and endogenous retinoid concentration in rats},
  issn      = {0890-6238},
  doi       = {10.1016/j.reprotox.2010.05.005},
  year      = {2010},
  abstract  = {Retinoids are essential in vertebrate reproduction and embryonic development. All-trans-retinoic acid (ATRA) is tightly regulated during these processes. CYP26A1 is mainly responsible for its degradation. To study the role of CYP26A1 during implantation, we applied R115866, a CYP26A1-specific antagonist, to rats during early gestation days (GD). On GD 6.5 and 12 samples were collected and the number of embryos was evaluated. ATRA concentration increased in uterus and serum, mRNA expression of CYP26A1 and CRABP2 increased in the liver, but not in the uterus. Uterine COX1 and 17 beta HSD mRNA expression was decreased. The number of embryos on GD 12 was not altered in this setting. It can be concluded that uterine expression of the analyzed retinoid-response genes during early gestation is not altered by this R115866 treatment and instead indirectly via ATRA. From our experiment we cannot confirm that ATRA obtains a major influencing role in the regulation of embryonic implantation.},
  language  = {en}
}
@article{RuhlFritzscheVermotetal.2006,
  author    = {Ruhl, R. and Fritzsche, Britta and Vermot, J. and Niederreither, K. and Neumann, U. and Schmidt, A. and Schweigert, Florian J. and Dolle, P.},
  title     = {Regulation of expression of the retinoic acid-synthesising enzymes retinaldehyde dehydrogenases in the uteri of ovariectomised mice after treatment with oestrogen, gestagen and their combination},
  year      = {2006},
  abstract  = {The active metabolite of vitaminA, retinoic acid (RA), plays an important role in the female reproductive system. The synthesis of RA is tightly regulated by the activity of retinaldehyde dehydrogenases (Raldh). Among these, Raldh1 and Raldh2 exhibit specific temporal and spatial expression patterns in the mouse uterus, both during the oestrous cycle and early pregnancy. In the present study, we have assessed whether oestradiol and progesterone directly influence the uterine expression of Raldh1 and Raldh2 in ovariectomised mice. We investigated the effect of gestagen (promegestone 0.3 mg kg(-1) bodyweight), oestrogen (oestradiol 3 mu g kg(-1) bodyweight) and their combination on the uterine expression of Raldh2. Expression was analysed using in situ hybridisation and quantified using real-time detection reverse transcription-polymerase chain reaction. The results show that the expression of Raldh2 is rapidly (within 1-4 h) induced in stromal cells by oestrogen, but not by gestagen, treatment, whereas combined oestrogen + gestagen treatment leads to a more prolonged (48 h) response. In contrast, oestrogen, but not progesterone, treatment downregulates (within 4 - 24 h) Raldh1 expression in the uterine glandular epithelium. We conclude that the uterine RA concentrations are regulated by oestrogens via an effect on the expression of the Raldh synthesising enzymes. Such a regulation is consistent with the natural fluctuations of Raldh expression during the oestrous cycle, early pregnancy and blastocyst implantation},
  language  = {en}
}