Animal Physiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany.
Behavioral Physiology and Sociobiology (Zoology II), Biozentrum, University of Würzburg, Würzburg, Germany.
J Comp Neurol. 2021 Jan;529(1):159-186. doi: 10.1002/cne.24941. Epub 2020 May 25.
The central complex (CX) in the insect brain is a higher order integration center that controls a number of behaviors, most prominently goal directed locomotion. The CX comprises the protocerebral bridge (PB), the upper division of the central body (CBU), the lower division of the central body (CBL), and the paired noduli (NO). Although spatial orientation has been extensively studied in honeybees at the behavioral level, most electrophysiological and anatomical analyses have been carried out in other insect species, leaving the morphology and physiology of neurons that constitute the CX in the honeybee mostly enigmatic. The goal of this study was to morphologically identify neuronal cell types of the CX in the honeybee Apis mellifera. By performing iontophoretic dye injections into the CX, we traced 16 subtypes of neuron that connect a subdivision of the CX with other regions in the bee's central brain, and eight subtypes that mainly interconnect different subdivisions of the CX. They establish extensive connections between the CX and the lateral complex, the superior protocerebrum and the posterior protocerebrum. Characterized neuron classes and subtypes are morphologically similar to those described in other insects, suggesting considerable conservation in the neural network relevant for orientation.
昆虫脑中的中央复合体 (CX) 是一个高级整合中心，控制着许多行为，其中最突出的是目标导向的运动。CX 由脑桥前体 (PB)、中央体上部分 (CBU)、中央体下部分 (CBL) 和成对的神经节 (NO) 组成。尽管在行为层面上已经对蜜蜂的空间定向进行了广泛研究，但大多数电生理和解剖分析都是在其他昆虫物种中进行的，这使得构成蜜蜂 CX 的神经元的形态和生理学在很大程度上仍是个谜。本研究的目的是对蜜蜂 Apis mellifera 的 CX 中的神经元细胞类型进行形态学鉴定。通过将离子导入染料注入 CX，我们追踪到了 16 种亚型的神经元，它们将 CX 的一个亚区与蜜蜂中央脑的其他区域连接起来，还有 8 种亚型主要将 CX 的不同亚区相互连接。它们在 CX 和侧复合器、上脑前体和后脑前体之间建立了广泛的联系。所描述的神经元类和亚型在形态上与在其他昆虫中描述的相似，这表明与定向相关的神经网络具有相当大的保守性。
