DRUG MECHANISM IN NEURONAL DOPAMINE ORGANIZATION

中脑的多巴胺能神经元，支配 在过去，端脑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 彻底改变了我们对中枢神经系统功能的理解发展和 我们已经研究了多巴胺能投射的正常维持， 实验室使用体外解离细胞再聚集系统， 所述单细胞悬浮液是从细胞的特定区域制备的， 胚胎小鼠的大脑可以自行重组， 与它们通常投射到的大脑其他区域的细胞 轴突并形成突触连接。该系统的主要优点是 它允许选择性地重建大脑皮层的神经通路， 胚胎脑中的神经元和神经胶质细胞可以继续其正常的 发育到成年阶段的模式非常类似于 在体内观察。重新聚合系统将用于检查角色 多巴胺能细胞存活中靶细胞和非靶细胞的大小 多巴胺能投射的特异性以及 会聚中脑和皮层输入调节DARRP-32 纹状体中型多刺神经元的磷酸化。另外我们有 开发了永生化的混合多巴胺能细胞系， 释放发射器。细胞系也已经从原代细胞中产生。 纹状体的神经元表达一系列功能性 多巴胺能受体和在某些情况下胆碱能表型。的 中脑多巴胺能和纹状体的递质表型 胆碱能永生化细胞在存在 非靶细胞（不从神经元接收突触连接的细胞） 这些细胞所来源的初级神经元）。下调 非靶点对永生化细胞的递质表型的影响可能是 在大脑发育中的功能意义，并将尝试 来识别参与这个过程的识别分子。新 包括引入温度调节的SV 40大型 T抗原，然后是体细胞杂交将用于 温度调控下中枢多巴胺能神经元的永生化 生长特性允许将这些细胞移植到 大脑将进行关于使用永生化克隆 多巴胺能细胞系，以及维持在 重组培养，作为神经元替代的细胞来源， 去神经损伤模型和自然发生的退化 多巴胺能神经元的数量。这些研究将 其目的在于检测永生化多巴胺能细胞系的效用， 以及重组培养系统的有用性， 用于在培养物中维持多巴胺能神经元延长的时间， 时间，这将是在需要时提供移植的目的， 在实验动物或人类疾病状态中。

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.