Chick sensory neurons grow to their correct targets in the hindlimb from the outset during normal development and following various experimental manipulations. This may result not because sensory neurons respond to specific limb-derived cues, but because they interact in some way with motoneurons which are responsive to such cues. To test this possibility, we removed the ventral part of the neu...

The branching structure of the stem dendrites of five motoneurons innervating the dorsal neck muscles, biventer cervicis and complexus, was examined in the adult cat using intracellular staining techniques. The dendritic tree of each motoneuron was reconstructed completely and then dissected into several parts, each corresponding to the branches. Twenty-five of the 49 stem dendrites examined ha...

Spinal motoneurons innervating skeletal muscle were amongst the first neurons shown to require the presence of their target cells to develop appropriately. Isolated embryonic chick and rat motoneurons have been used to identify neurotrophic factors and cytokines capable of supporting the survival of developing motoneurons. Such factors include ciliary neurotrophic factor (CNTF), which is presen...

A single spinal motoneuron receives tens of thousands of synapses. The neurotransmitters riving potential of the linear sum ct of this non-linearity on the current delivered to the soma during activation of predetermined numbers and distributions of excitatory and inhibitory synapses. To accomplish this goal we constructed compartmental models constrained by detailed measurements of the geometr...

Gonzalez, Michael and William F. Collins, III. Modulation of whereas Type S motoneurons are able to dictate motor unit motoneuron excitability by brain-derived neurotrophic factor. J. contractile speed via an orthodromic mechanism (for review, Neurophysiol. 77: 502–506, 1997. The influence of neurotrophins see Mendell et al. 1994). on motoneuron survival and development has been well docuRecent...

Introduction Several coding stages occur in the nervous system when an internal decision is reached to enact a certain movement. The desired movement is coded into spike trains of a large number of neurons in prefrontal, premotor and suplementary motor cortices as well as in other areas such as the basal ganglia and cerebellum. These spike trains can be assembled in a column vector x(t), each e...

BACKGROUND The mechanisms responsible for generating rhythmic motor activity in the developing spinal cord of the chick embryo are poorly understood. Here we investigate whether the activity of motoneurons occurs before other neuronal populations at the beginning of each cycle of rhythmic discharge. METHODOLOGY/PRINCIPAL FINDINGS The spatiotemporal organization of neural activity in transvers...

Electrical transmission among neurons has been considered a mechanism to synchronize neuronal activity, and rectification provides a mechanism to confine the flow of signals among the connected neurons. The question is how this type of transmission operates within complex neuronal networks. In the leech, the neurons located in position 151 of the midbody ganglion map are connected to virtually ...

Several protocols direct human embryonic stem cells (hESCs) toward differentiation into functional motoneurons, but the efficiency of motoneuron generation varies based on the human ESC line used. We aimed to develop a novel protocol to increase the formation of motoneurons from human ESCs. In this study, we tested a nuclear histone deacetylase protein, Sirt1, to promote neural precursor cell (...