Study of the hierarchy organization on the central pattern generator for locomotion in the cat.

用Nialamide和L-DOPA刺激猫中枢模式产生器（CPG），分别从颈、前肢、躯干和后肢的神经记录脊髓分离前后的神经图。后肢肌肉的CPG比其他部位的CPG更具独立性。前肢的CPG受到后肢CPG的抑制作用。颈部尾部的CPG促进了颈部的CPG。用金属电极电刺激中脑运动区，诱导位于颈部、躯干和后肢的CPG的节律性活动。MLR刺激产生的颈干肌肉神经节律性活动与后肢肌肉神经节律性活动一致。MLR刺激后后肢肌神经活动发生率高于颈、干肌神经。这些差异表明，在颈部、躯干或后肢肌肉的CPGs之间可能存在等级组织。电刺激MLR后，记录支配最长肌的第一、三、五腰椎神经的神经图。第1神经节律性活动发生率高于第3神经，第5神经无节律性活动。这一事实表明，在肌肉中控制运动节律的CPG可能是分离的，它们的优势可能存在差异。

The feline central pattern generator (CPG) was stimulated with Nialamide and L-DOPA and the neurograms were recorded from the nerves of neck, forelimb, trunk and hindlimb before and after dissection of several parts of the spinal cord. The CPG of the hindlimb muscle was more independent than the CPGs of other locations. The CPG of the forelimb received an inhibitory effect from the CPG of the hindlimb. The CPG of the neck was facilitated by the CPG of caudal parts from the neck.The midbrain locomotor region (MLR) was stimulated electrically with a metal electrode to induce the rhythmic activity from the CPG located in the neck, trunk and hindlimb. The MLR stimulation produced the rhythmic activity in the neck and trunk muscle nerves coincident with that in the hindlimb muscle nerve. The occurrence rate of activity in hindlimb muscle nerve after stimulation of the MLR was higher than that in the neck or trunk muscle nerves. These differences indicated that there might be a hierarchic organization among the CPGs in neck, trunk or hindlimb muscles. After electric stimulation of the MLR,the neurograms of the 1st, 3rd and 5th lumbar nerves innervating the longissimus were recorded. The occurrence rate of rhythmic activity in the 1st nerve was higher than that in the 3rd nerve and there was no occurrence in the 5th nerves. This fact indicated that the CPG making the locomoting rhythm in a muscle might be separated and there might be difference in their dominance.