Department of Physics, Washington University in St. Louis, St. Louis, MO 63130-4899, USA.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2010 Apr;196(4):249-62. doi: 10.1007/s00359-010-0511-y. Epub 2010 Feb 24.
The frog nucleus isthmi (parabigeminal nucleus in mammals) is a visually responsive, cholinergic and anatomically well-defined group of neurons in the midbrain. It shares reciprocal topographic projections with the ipsilateral optic tectum (superior colliculus in mammals) and strongly influences visual processing. Anatomical and biochemical information indicates the existence of distinct neural populations within the frog nucleus isthmi, which raises the question: are there electrophysiological distinctions between neurons that are putatively classified by their anatomical and biochemical properties? To address this question, we measured frog nucleus isthmi neuron cellular properties in vitro and visual response properties in vivo. No evidence for distinct electrophysiological classes of neurons was found. We thus conclude that, despite the anatomical and biochemical differences, the cells of the frog nucleus isthmi respond homogeneously to both current injections and simple visual stimuli.
青蛙脑桥核（哺乳动物中的成对内侧脑核）是中脑中一群具有视觉反应性、胆碱能和解剖学特征的神经元。它与同侧视顶盖（哺乳动物中的上丘）有相互的拓扑投射关系，并强烈影响视觉处理。解剖学和生物化学信息表明，青蛙脑桥核内存在着不同的神经群体，这就提出了一个问题：是否存在电生理上的区别，这些神经元根据其解剖学和生物化学特性被假定分类？为了解决这个问题，我们在体外测量了青蛙脑桥核神经元的细胞特性，并在体内测量了视觉反应特性。没有发现神经元具有明显电生理类别的证据。因此，我们得出结论，尽管存在解剖学和生物化学上的差异，但青蛙脑桥核的细胞对电流注入和简单视觉刺激的反应是一致的。
