Kleinhaus A L, Angstadt J D
Department of Cell Biology and Anatomy, New York Medical College, Valhalla, New York 10595, USA.
J Neurobiol. 1995 Jul;27(3):419-33. doi: 10.1002/neu.480270313.
A complete understanding of animal behavior at the cellular level requires detailed information on the intrinsic biophysical properties of neurons, muscles, and the synaptic connections they make. In the past 10 to 15 years, electrophysiological studies of leech neurons have revealed a diverse array of voltage-gated ionic conductances distinguished by their pharmacological sensitivity to classic ion channel blockers. Voltage-clamp studies have provided new information about the kinetics and voltage-dependence of Na+ conductances, several K+ currents, including IA, IK and IK(Ca.), and high- and low-voltage-gated Ca2+ conductances. These studies showed that the action potentials of most leech neurons result from the usual sequence of permeability changes to Na+, K+, and Ca2+ ions. They also added insight as to the role played by particular combinations of conductances in providing individual neurons with electrical properties appropriate for the particular information they encode. Evidence is accumulating on the modulatory actions fo endogenous neurotransmitters such as FMRFamide, serotonin, and octopamine on motor behaviors in the animal. Parallel studies suggest that changes in behavior can be explained, at least in part, by the alteration of firing patterns of selected neurons and muscles resulting from modulation of multiple ion conductances. This makes the leech exceptionally attractive for neuroethological studies because it is one of the simplest organisms in which the methods of psychology and neurobiology can be combined. Information gathered from this animal will therefore increase our understanding regarding general principles underlying the cellular basis of behavior.
要在细胞水平上全面理解动物行为，需要详细了解神经元、肌肉及其形成的突触连接的内在生物物理特性。在过去的10到15年里，对水蛭神经元的电生理研究揭示了各种各样的电压门控离子电导，它们对经典离子通道阻滞剂的药理敏感性各不相同。电压钳研究提供了关于Na+电导、几种K+电流（包括IA、IK和IK(Ca.)）以及高电压和低电压门控Ca2+电导的动力学和电压依赖性的新信息。这些研究表明，大多数水蛭神经元的动作电位是由对Na+、K+和Ca2+离子通透性变化的通常顺序产生的。它们还深入了解了特定电导组合在为单个神经元提供适合其编码的特定信息的电特性方面所起的作用。越来越多的证据表明，内源性神经递质如FMRF酰胺、血清素和章鱼胺对动物运动行为具有调节作用。平行研究表明，行为的变化至少部分可以通过多种离子电导的调节导致选定神经元和肌肉放电模式的改变来解释。这使得水蛭成为神经行为学研究特别有吸引力的对象，因为它是最简单的生物之一，可以将心理学和神经生物学方法结合起来。因此，从这种动物身上收集到的信息将增进我们对行为细胞基础的一般原则的理解。
