DRUG MECHANISM IN NEURONAL DOPAMINE ORGANIZATION

中脑的多巴胺能神经元，支配 端脑，在过去一直是密集调查的焦点 三十年来，从这些研究中获得的信息已经 彻底改变了我们对中枢神经系统功能的理解。中国的发展和 多巴胺能投射的正常维持已经在我们的 实验室使用体外分离的细胞重聚集系统 哪些单细胞悬浮液是从特定区域制备的 胚胎小鼠的大脑可以自行重组，也可以 它们通常投射到的大脑其他区域的细胞 并形成突触连接。这个系统的主要优点是 它允许选择性地重建大脑的神经通路 胚胎脑中的神经元和神经胶质细胞可以继续保持正常 发育到成体阶段的模式与 活体观察。将使用重新聚合系统来检查角色 靶细胞和非靶细胞在多巴胺能细胞存活和大小中的作用 多巴胺能投射的特异性以及 汇聚的中脑和皮质传入对DARRP-32的调节 纹状体中棘神经元的磷酸化。此外，我们还有 开发出永生化杂交多巴胺能细胞系，可产生和 松开发射机。细胞系也是从原代培养出来的 纹状体的神经元表达一系列功能性的 多巴胺能受体，在某些情况下是胆碱能表型。这个 中脑多巴胺能和纹状体的递质表型 胆碱能永生化细胞显著减少 非靶细胞(不接受来自 这些细胞来自的初级神经元)。下调监管 非靶细胞永生化细胞的递质表型可能是 脑发育的功能意义，并将尝试 以确定参与这一过程的识别分子。新的 引进温控SV40大型变送器的几种方法 T抗原和体细胞杂交将用于 恒温诱导中枢多巴胺能神经元永生化 生长特性允许将这些细胞移植到 大脑。将对永生化克隆的使用进行研究 多巴胺能细胞系，以及维持在 重组培养作为神经细胞替代的细胞来源 去神经和自然退行性变的损伤模型 织布工突变小鼠的多巴胺能神经元。这样的研究将是 旨在研究永生化的多巴胺能细胞系的用途， 以及重组文化系统作为一种手段的有用性 用于在培养中长期维持多巴胺能神经元 时间，然后根据需要为移植目的提供时间 无论是在实验动物还是在人类疾病状态下。

The dopaminergic neurons of the mesencephalon, innervating the telencephalon, have been the focus of intense investigation over the past three decades, and the information derived from such studies has revolutionized our understanding of CNS function. The development and normal maintenance of the dopaminergic projections has been studied in our laboratory using an in vitro dissociated cell-reaggregation system in which single cell suspensions prepared from specific areas of the embryonic mouse brain are allowed to reaggregate either by themselves or with cells from other areas of the brain to which they normally project axons and form synaptic connections. The primary advantage of this system is that it permits a selective reconstruction of neuronal pathways of the embryonic brain in which the neurons and glia can continue their normal development to the adult stage in a pattern remarkably similar to that observed in vivo. The reaggregate system will be used to examine the role of target and nontarget cells in dopaminergic cell survival and the size and specificity of the dopaminergic projections as well as the role of convergent mesencephalic and cortical inputs in regulating DARRP-32 phosphorylation in striatal medium spiny neurons. In addition, we have developed immortalized hybrid dopaminergic cell lines which produce and release the transmitter. Cell lines have also been generated from primary neurons of the corpus striatum which express an array of functional dopaminergic receptors and in some cases a cholinergic phenotype. The transmitter phenotype of both the mesencephalic dopaminergic and striatal cholinergic immortalized cells is markedly reduced in the presence of nontarget cells (cells which do not receive synaptic connections from the primary neurons from which these cells are derived). The down-regulation of the transmitter phenotype of immortalized cells by nontargets may be of functional significance in brain development and an attempt will be made to identify the recognition molecules involved in this process. New approaches involving introduction of the temperature-regulated SV40 large T antigen followed by somatic cell hybridization will be used for the immortalization of central dopaminergic neurons with temperature-regulated growth characteristics permitting the transplantation of these cells into the brain. Studies will be undertaken on the use of immortalized clonal dopaminergic cell lines, as well as mature dopamine neurons maintained in reaggregate culture, as a source of cells for neuronal replacement in lesion models of denervation and in the naturally occurring degeneration of dopaminergic neurons in the weaver mutant mouse. Such studies will be directed at examining the utility of immortalized dopaminergic cell lines, as well as the usefulness of the reaggregate culture system, as a means for maintaining dopaminergic neurons in culture for extended periods of time, which would then be available on demand for transplantation purposes in either experimental animals or in human disease states.