STRESS ALLOSTASIS: CRF, SEROTONIN AND THE BNST

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 2007年，我们完成了我们的研究，证明多个5-羟色胺受体在BNST神经元的不同亚群中表达。我们不仅有生理数据表明单个BNST神经元可以表达多种受体，而且在2007年，我们还开发了一种技术(单细胞RT-PCR)，可以从单个神经元中提取mRNA，并检测它们的5HT受体基因图谱。 我们还完成了对单个BNST神经元表达的固有膜电流的检查。我们鉴定了BNST中至少三种不同的细胞类型(I-III型)。在电流钳制模式下，这三种亚型对去极化电流注入的反应表现出特有的动作电位激发模式，而对超极化电流注入则表现出明显的电压响应。电流钳数据表明，根据BNST神经元对特定固有膜电流的表达模式，可以进一步区分BNST神经元的三个亚型。我们还开始研究塑造BNST神经元放电模式的离子通道的遗传基础。我们使用了同样的单细胞RT-PCR技术来检测BNST神经元中表达的离子通道亚基。到目前为止，我们已经鉴定了至少5个IA通道亚基、3个IT通道亚基和2个IH通道亚基。这些亚基中的每一个都有不同的动力学分布和电导，以及在细胞内的不同分布。因此，这些不同的离子通道亚单位的组合可以微妙地、但显著地影响这些神经元的放电模式。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. In 2007 we completed our study demonstrating that multiple 5HT receptors are expressed in distinct subpopulations of BNST neurons. Not only do we have physiologic data showing that individual BNST neurons can express more than one receptor, in 2007 we also developed a technique (single cell RT-PCR) whereby we can extract the mRNA from individual neurons and examine their genetic 5HT receptor profile. We also completed our examination of the intrinsic membrane currents that are expressed by individual BNST neurons. We identified at least three distinct cell types in the BNST (Types I - III). In current-clamp mode, these three subtypes show characteristic action potential firing patterns in response to depolarizing current injection, as well as showing a distinct voltage response to hyperpolarizing current injection. The current clamp data suggested that the three subtypes of BNST neuron could be further differentiated based on their expression patterns for specific intrinsic membrane currents. We also began examination of the genetic underpinning for the ion channels that shape the firing pattern of BNST neurons. We employed the same single cell RT-PCR technique to examine the ion channel subunits that are expressed in BNST neurons. To date we have characterized at least 5 IA channel subunits, 3 IT channel subunits and 2 IH channel subunits. Each of these subunits has a different kinetic profile and conductance, as well as a differential distribution within the cell. Hence, the combination of these different ion channel subunits can subtly, but dramatically, influence the firing pattern of these neurons.