Acta clinica Croatica, Vol. 43 No. 2, 2004.
Conference paper
Mammalian Embryo in Organ Culture in Vitro as a Basic Model for Preclinical Studies in Human Neurogenesis
Vesna Crnek-Kunstelj
Jagoda Stipić
Tomislav Zeljko
Abstract
Modified organ culture of mammalian postimplantation embryo developed in our laboratory provides favorable conditions for terminal differentiation of the main tissues of gastrulating embryo, including nerve tissue. Intracellular signals provided by growth and neurotrophic factors play a crucial role during neurogenesis. In the present study, the role of retinoic acid (RA), fibroblast growth factor (FGF) and nerve growth factor (NGF) in neural tissue differentiation was investigated in cultivated 9.5-day-old rat embryo in the critical period of mammalian development, gastrulation. The proper embryonic part of the whole embryo without extraembryonic membranes was cultivated in air-liquid interface for two weeks. To study the effect of neural tissue-inducing agents, various concentrations of RA, FGF, NGF and FGF/NGF combinations were added to the basic culture medium within the time frame of 9 days. The embryos developed into teratoma-like structures, and then they were fixed and histologically examined for the presence of neural tissue. RA and NGF did not improve neural tissue differentiation. However, its proportion was significantly higher in FGF-treated embryos. FGF is less effective in the presence of NGF at the very beginning of neural tissue differentiation. It seems that NGF hinders the stimulating effect of FGF. In our experimental model, neural tissue differentiation is probably initially regulated by FGF signal, although there is evidence that RA and NGF signals are also needed later in development. Our model system has the advantage of being simpler than the embryo in vivo but closer to normal development than cell cultures. Therefore, our results are in accordance with the idea that FGF is a neural inducer in the vertebrates.
Keywords
Nervous system - embryology; Animal; Nerve growth factor; Fibroblast growth factors
Hrčak ID:
15161
URI
Publication date:
1.6.2004.
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