McClellan A D, Grillner S
Brain Res. 1983 Jun 20;269(2):237-50. doi: 10.1016/0006-8993(83)90133-6.
An in vitro preparation has been developed in which the caudal part of the lamprey spinal cord (resting on the notochord) is still innervating the tail fin. Mechanical stimulation of the tail fin elicits ventral root activity that would normally lead to an initial body flexure (tail fin withdrawal) followed by escape swimming. These patterns of ventral root activity are correlated with motor activity and movements elicited by a similar tail fin stimulus in intact and spinal lampreys. The ascending control systems activated by tail fin stimulation consists of long axons which project for at least 20 segments, and are not dependent on propagation through local circuits in the gray matter. Sensory input activated by passive bending of the notochord/spinal cord in the in vitro preparation gates the tail fin withdrawal motor activity, such that tail fin stimulation elicits ventral root bursts on the same side as the direction of bending. This new in vitro preparation survives for several days and will provide new opportunities to study the normal initiation and coordination of two different patterns of behavior, swimming and withdrawal.
已经开发出一种体外制备方法，其中七鳃鳗脊髓的尾部（位于脊索上）仍在支配尾鳍。对尾鳍的机械刺激会引发腹根活动，这种活动通常会导致身体最初的弯曲（尾鳍撤回），随后是逃避游泳。这些腹根活动模式与完整和脊髓损伤的七鳃鳗中类似尾鳍刺激所引发的运动活动和动作相关。由尾鳍刺激激活的上行控制系统由至少投射20个节段的长轴突组成，并且不依赖于通过灰质中的局部回路进行传播。在体外制备中，由脊索/脊髓被动弯曲激活的感觉输入控制尾鳍撤回运动活动，使得尾鳍刺激在与弯曲方向相同的一侧引发腹根爆发。这种新的体外制备可以存活数天，并将为研究游泳和撤回这两种不同行为模式的正常起始和协调提供新的机会。
