Saltin Brian D, Goldsmith Clarus, Haustein Moritz, Büschges Ansgar, Szczecinski Nicholas S, Blanke Alexander
Bonn Institute of Organismic Biology, University of Bonn, Bonn, Germany.
Department of Mechanical, Materials, and Aerospace Engineering, Benjamin M. Statler College of Engineering and Mineral Resources, West Virginia University, Morgantown, WV, USA.
J R Soc Interface. 2025 May;22(226):20240559. doi: 10.1098/rsif.2024.0559. Epub 2025 May 7.
Campaniform sensilla (CS) are mechanosensors embedded in the cuticle of insects. They are often found at locations near the joints of leg segments. On legs, CS are generally considered to respond directionally to cuticle bending during legged locomotion. It is currently unclear how CS locations affect strain levels at the CS, but this information is crucial for understanding how CS respond to stimuli. Here we present a parametric finite element model of the femoral CS field for hind legs with 12 general and seven CS-specific parameters each. This model allows testing how changes in CS location, orientation and material property affect strain levels at each CS. We used experimentally acquired kinematic data and computed ground reaction forces to simulate -like forward stepping. The displacements found in this study at the physiological CS field location near the trochanter-femur joint are smaller than those necessary for conformation changes of ion channels involved in signal elicitation. Also, variation of material properties of the CS had little influence on displacement magnitudes at the CS cap where the sensory neuron attaches. Thus, our results indicate that ground reaction forces alone are unlikely to serve CS field activation during forward walking.
钟形感器(CS)是嵌入昆虫角质层的机械传感器。它们常出现在腿部节段关节附近的位置。在腿部,一般认为钟形感器在有腿运动过程中对角质层弯曲产生定向反应。目前尚不清楚钟形感器的位置如何影响其应变水平,但这些信息对于理解钟形感器如何对刺激做出反应至关重要。在此,我们提出了一个后腿股骨钟形感器场的参数化有限元模型,每个模型有12个通用参数和7个特定于钟形感器的参数。该模型可以测试钟形感器位置、方向和材料属性的变化如何影响每个钟形感器的应变水平。我们使用实验获取的运动学数据并计算地面反作用力来模拟类似向前迈步的过程。本研究中在转子 - 股骨关节附近生理钟形感器场位置发现的位移小于信号激发所涉及的离子通道构象变化所需的位移。此外,钟形感器材料属性的变化对感觉神经元附着的钟形感器帽处的位移大小影响很小。因此,我们的结果表明,仅地面反作用力不太可能在向前行走过程中激活钟形感器场。