DISCHARGE PATTERNS OF MOTONEURONS

这项研究的长期目标是确定 介导初级传入去极化的中间神经元 猫脊髓的肌肉和皮肤传入纤维(PAD) 绳索，并更准确地定义到 它们是属于的，也是调节 他们的活动。实验将在麻醉状态下进行， 去大脑和去大脑/脊椎猫，自发或 瘫痪并处于人工呼吸状态。特别关注 将致力于：a)，细胞内垫的特征 分段输入和降序输入产生的图案 生理鉴定的单一Ia、Ib和II组传入 与内侧腓肠肌(MG)相继的纤维 肌肉，在正常准备和1周至9个月之间 在切断MG神经并重新缝合后。B)，以确定是否 皮肤纤维的兴奋和抑制作用 在Ib垫上，纤维受脊髓上张力的调制 下降的影响。C)，以描述可能的 直流电势变化与钾瞬变的关系 通过刺激皮肤纤维产生的垫子 脊髓上核与药物阻断GABA能的作用 以及垫上的5-羟色胺能传递。D)，以调查 单个中间核中间神经元在中枢神经系统中的作用 运动神经元突触电位和背根电位 由组1和皮肤抽搐引起，e)，以揭示 可能参与神经递质抑制作用的递质 运动神经元的中间核中间神经元和f)，分析 单根La纤维引起的单突触EPSP的涨落 脊髓MG运动神经元在不同程度的牵张 协同和拮抗肌肉和在电的过程中 刺激运动神经产生LA-EPSPS抑制。

The long term goals of this research are to identify the interneurons which mediate the primary afferent depolarization (PAD) of muscle and cutaneous afferent fibers in the cat spinal cord, and to define more precisely the reflex pathways to which they belong, as well as the supraspinal influences which modulate their activity. Experiments will be performed in anesthetized, decerebrated and decerebrated/spinal cats, either spontaneously or paralyzed and under artificial respiration. Particular attention will be given to: a), characterization of the intracellular PAD patterns produced by segmental and descending inputs on physiologically identified single group Ia, Ib and II afferent fibers left in continuity with the medial gastrocnemius (MG) muscle, both in normal preparations and between 1 week and 9 months after sectioning and resuturing the MG nerve. b), to determine if the excitatory and inhibitory actions that cutaneous fibers have on the PAD of Ib fibers are modulated by supraspinal tonic descending influences. c), to characterize the possible correlation of the DC potential changes and potassium transients with the PAD of cutaneous fibers produced by stimulation of supraspinal nuclei, and the effects of drugs blocking GABAergic and serotonergic transmission on the PAD. d), to investigate the actions of single intermediate nucleus interneurons on the motoneuron synaptic potentials and on dorsal root potentials elicited by group 1 and by cutaneous volleys, e), to disclose the transmitters possibly involved in the inhibitory actions of intermediate nucleus interneurons on motoneurons and f), analyze the fluctuations of monosynaptic EPSPs elicited by single la fibers in spinal MG motoneurons during various amounts of stretch of synergistic and antagonistic muscles and during electrical stimulation of motor nerves producing depression of la-EPSPs.