Doctoral Training Centre in Neuroinformatics and Neural Computation, University of Edinburgh, 10 Crichton St., Edinburgh, UK.
Network. 2011;22(1-4):133-42. doi: 10.3109/0954898X.2011.638967.
Crayfish (Astacus astacus) muscle stretch receptors show strong homology to mammalian muscle spindles and bipolar neurons in D. melanogaster. All are typical, non-ciliated, stretch-sensitive, afferent neurons. Such receptors are observed in many species and perform an important sensory role. However, they are poorly characterised. A previous study reported a bio-mechanical and behavioural model of A. astacus stretch receptors, which used the principles of elasticity and tension in a spring to describe the adaptation of a mechano-sensory ending. This model described the changing mechano-sensory currents in the receptor when subjected to a stretch protocol. Here, we re-implement and extend this model. Notably, we introduce additional descriptions of voltage-gated channels that are suggested to contribute to stretch receptor mechano-transduction. Our model presents a more complete picture of the initiation of the mechano-receptor potential in response to a stretching stimulus. The inclusion of voltage-dependent sodium and potassium currents in addition to the initial mechano-sensitive sodium current allowed the model to account for most of the initial stretch response of the receptor. This preliminary model has potential for extension to describe fully the behaviour of non-ciliated mechano-sensors across species and predict the molecular mediators of mechano-transduction.
螯虾（Astacus astacus）肌肉牵张感受器与哺乳动物肌梭和黑腹果蝇中的双极神经元具有很强的同源性。它们都是典型的、无纤毛的、对牵张敏感的传入神经元。这种感受器在许多物种中都有观察到，并且具有重要的感觉作用。然而，它们的特征描述很差。之前的一项研究报道了螯虾牵张感受器的一种生物力学和行为模型，该模型使用了弹性和张力的原理来描述机械感觉末梢的适应。该模型描述了在拉伸方案下，感受器中不断变化的机械感觉电流。在这里，我们重新实现并扩展了这个模型。值得注意的是，我们引入了附加的电压门控通道描述，这些通道被认为有助于牵张感受器的机械转导。我们的模型更全面地描述了机械感受器电位在拉伸刺激下的起始过程。除了初始的机械敏感钠电流外，还包括电压依赖性的钠和钾电流，使模型能够解释感受器的大部分初始拉伸反应。这个初步模型具有扩展的潜力，可以描述跨物种的无纤毛机械感受器的行为，并预测机械转导的分子介质。
