RUI: The Role of Multiple Modulators in a Small Neural System: A Comparative Approach

动物必须改变它们的行为以适应不断变化的环境。在驱动有节奏运动（如运动和咀嚼）的模式生成器中，允许这种行为灵活性的一种机制是神经调节剂对神经网络的功能重新配置。在甲壳类动物的前肠中，口胃系统包含驱动幽门过滤器和胃磨坊的模式发生器，为研究神经调节提供了一个理想的系统。口胃系统中的模式发生器和调节输入都已被广泛表征。在这个神经节中已经发现了20多种调节物质，这就提出了以下问题：为什么这么多的调节剂参与调节这样一个相对简单的系统？该项目询问比较方法是否可以阐明这个问题，从而提供对神经调节剂的基本机制和作用的见解。在许多不同种类的十足甲壳类动物中，对幽门模式及其对调节剂的响应进行了一定程度的研究。本研究将进一步研究六种物种——两种密切相关的螃蟹，两种相关的龙虾，加利福尼亚多刺龙虾和一种海带蟹——对四种神经调节剂的反应。使用标准的记录技术，基本的幽门模式及其对这些物质的反应将被定性和定量地记录和表征。此外，将比较一些参与调节的机制，以及这四种调节剂对六种动物肌肉活动和收缩的影响。

Animals must alter their behavior to meet the demands of a changing environment. One mechanism that allows such behavioral flexibility in the pattern generators that drive rhythmical movements, such as locomotion and chewing, is the functional reconfiguration of neural networks by neuromodulators. The stomatogastric system, which contains the pattern generators that drive the pyloric filter and the gastric mill in the crustacean foregut, provides an ideal system in which to study neuromodulation. Both the pattern generators and the modulatory inputs in the stomatogastric system have been extensively characterized. More than 20 modulatory substances have been identified in this ganglion, raising the following question: Why are so many modulators involved in modulating such a relatively simple system? This project asks whether a comparative approach can shed light on this question and thus provide insights into the fundamental mechanisms and effects of neuromodulators.The pyloric pattern and its responses to modulators have been studied to some extent in a number of different species of decapod crustaceans. The present study will further examine the responses of six species - two closely related species of crab, two related lobster species, the California spiny lobster, and a kelp crab - to a test group of four neuromodulators. Using standard recording techniques, the basic pyloric pattern and its responses to these substances will be recorded and characterized qualitatively and quantitatively. Additionally, some of the mechanisms involved in modulation will be compared, as will the effects of these four modulators on muscle activity and contraction in the six species.