Humpel C, Johansson M, Marksteiner J, Saria A, Strömberg I
Neurochemistry Unit, Department of Psychiatry, Innsbruck, Austria.
Regul Pept. 1995 Mar 7;56(1):9-17. doi: 10.1016/0167-0115(95)00122-r.
In oculo transplantation provides a powerful tool to study development and gene expression of isolated brain regions. In this study we grafted striatal and mesencephalic brain tissue to the anterior eye chamber and allowed it to survive for 2 and 6 weeks. Striatal or mesencephalic pieces were either grafted alone (single grafts) or together in close connection (co-grafts). As a control normal adult untreated rats were analyzed at the striatal and hippocampal level. Using non-radioactive in situ hybridization with digoxigenin-labeled riboprobes we detected preprotachykinin-A mRNA, a neuropeptide marker for striatal neurons. We report that adult normal rats show a strong expression of preprotachykinin-A mRNA in the striatum, medial habenula and piriform cortex, verifying the specificity of the method. Mesencephalic in oculo grafts did not reveal any staining for preprotachykinin-A mRNA. In single striatal grafts only a very weak expression of preprotachykinin-A mRNA was found at both time points investigated. Co-grafts grown for 2 weeks were not different from single striatal grafts, however, when striatum was grown together with ventral mesencephalon for 6 weeks the level of preprotachykinin-A mRNA was strong and near normal adult levels. We conclude that the mesencephalic dopaminergic innervation to the striatum might be a potent stimulus to neurons expressing preprotachykinin-A mRNA.
眼内移植为研究孤立脑区的发育和基因表达提供了一个强大的工具。在本研究中，我们将纹状体和中脑脑组织移植到眼前房，并使其存活2周和6周。纹状体或中脑组织块单独移植（单移植）或紧密连接在一起移植（共移植）。作为对照，对未经处理的正常成年大鼠的纹状体和海马水平进行分析。使用地高辛标记的核糖探针进行非放射性原位杂交，我们检测到前速激肽原-A mRNA，这是纹状体神经元的一种神经肽标记物。我们报告，成年正常大鼠在纹状体、内侧缰核和梨状皮质中显示出前速激肽原-A mRNA的强烈表达，证实了该方法的特异性。眼内中脑移植未显示前速激肽原-A mRNA的任何染色。在单纹状体移植中，在所研究的两个时间点仅发现前速激肽原-A mRNA的非常弱的表达。生长2周的共移植与单纹状体移植没有差异，然而，当纹状体与腹侧中脑一起生长6周时，前速激肽原-A mRNA的水平很强且接近成年正常水平。我们得出结论，中脑对纹状体的多巴胺能神经支配可能是对表达前速激肽原-A mRNA的神经元的一种有效刺激。
