Baierlein Brittany, Thurow Alison L, Atwood Harold L, Cooper Robin L
Department of Biology, University of Kentucky, KY, USA.
J Vis Exp. 2011 Jan 18(47):2322. doi: 10.3791/2322.
The purpose of this report is to help develop an understanding of the effects caused by ion gradients across a biological membrane. Two aspects that influence a cell's membrane potential and which we address in these experiments are: (1) Ion concentration of K+ on the outside of the membrane, and (2) the permeability of the membrane to specific ions. The crayfish abdominal extensor muscles are in groupings with some being tonic (slow) and others phasic (fast) in their biochemical and physiological phenotypes, as well as in their structure; the motor neurons that innervate these muscles are correspondingly different in functional characteristics. We use these muscles as well as the superficial, tonic abdominal flexor muscle to demonstrate properties in synaptic transmission. In addition, we introduce a sensory-CNS-motor neuron-muscle circuit to demonstrate the effect of cuticular sensory stimulation as well as the influence of neuromodulators on certain aspects of the circuit. With the techniques obtained in this exercise, one can begin to answer many questions remaining in other experimental preparations as well as in physiological applications related to medicine and health. We have demonstrated the usefulness of model invertebrate preparations to address fundamental questions pertinent to all animals.
本报告的目的是帮助人们理解跨生物膜离子梯度所产生的影响。在这些实验中，我们探讨影响细胞膜电位的两个方面：（1）膜外K⁺的离子浓度，以及（2）膜对特定离子的通透性。小龙虾腹部伸肌按生化和生理表型以及结构可分为不同类型，有些是紧张性（慢）的，有些是相位性（快）的；支配这些肌肉的运动神经元在功能特性上也相应不同。我们利用这些肌肉以及浅表的紧张性腹部屈肌来演示突触传递的特性。此外，我们引入一个感觉-中枢神经系统-运动神经元-肌肉回路，以演示表皮感觉刺激的作用以及神经调节剂对该回路某些方面的影响。通过本实验所掌握的技术，人们可以开始回答其他实验制剂以及与医学和健康相关的生理学应用中仍存在的许多问题。我们已经证明了无脊椎动物模型制剂在解决与所有动物相关的基本问题方面的有用性。
