Synaptische Transmission zwischen Mitralzelle und Körperzelle im olfaktorischen Bulbus der Ratte: Zwei-Photonen-Mikroskopie der synaptischen Calciumströme und simultane Elektrophysiologie in vitro

该项目旨在更好地理解早期嗅觉加工，其中二尖瓣细胞和颗粒细胞之间的大树突互反突触是主要参与者。我们的方法将基于钙动力学的双光子成像和体外突触传递的常规电生理学的同时应用。鉴于在系统水平上理解球茎中嗅觉信息处理的本质这一长期目标，提出了以下研究方向：在研究了二尖瓣细胞-颗粒细胞突触刺激后的钙动力学后，我们将测量情绪和觉醒相关的神经调节剂去甲肾上腺素对钙瞬态和突触传递的影响，因为有强烈的神经调节投射到嗅球。最后，我们计划在更完整的电路中研究二尖瓣细胞-颗粒细胞互反突触的传递，以进一步阐明离心输入对嗅球信号处理的影响。为此，我们将开发一种“综合”切片制剂，其中也包含球外元素，即部分嗅觉皮层。

The proposed project aims at a better understanding of early olfactory processing, in which the large dendrodendritic reciprocal synapse between mitral cells and granule cells is a main player. Our approach will be based on simultaneous application of two-photon imaging of calcium dynamics and conventional electrophysiology of synaptic transmission in vitro. Given a long-term goal of understanding the nature of processing of olfactory information in the bulb at a systemic level, the following lines of research are proposed: Having investigated the calcium dynamics following stimulation of the mitral cell-granule cell synapse, we will measure the influence of the emotion- and arousal-related neuromodulator norepinephrine on calcium transients and synaptic transmission in this synapse, since there are strong neuromodulatory projections into the olfactory bulb. Finally, we plan to investigate transmission at the mitral cell-granule cell reciprocal synapse in the context of a more intact circuit, in order to further elucidate the influence of centrifugal inputs on signal processing in the olfactory bulb. To do so, we will develop an "integrative" slice preparation containing also extrabulbar elements, i.e. part of the olfactory cortex.