Laurent Vinay

..g. deficits in motor coordination--might have their roots in the prenatal period, in particular serotonin depletion due to exposure to several environmental and toxicological factors during pregnancy...

..This latter situation is observed early during development and in several pathological conditions, such as epilepsy, neuronal injury and chronic pain...

..This may be a critical factor in the development of posture and locomotion...

..The spontaneous embryonic and neonatal network-driven activity, detected at the levels of motoneurons and primary afferent terminals, may play a role in neuronal maturation and in the formation and refinement of sensorimotor connections...

..These pathways, through the neurotransmitters they contain, especially monoamines, are essential for the expression of some neuronal properties and may regulate several ongoing developmental processes...

..We conclude that the plasticity of GlyR is independent of supraspinal influences whereas that of GABA(A)R is markedly influenced by descending pathways, in particular serotoninergic projections...

..Here, we review some recent data regarding chloride homeostasis in the spinal cord and its contribution to network operation involved in locomotion...

..We conclude that neuronal networks within the spinal cord are more excitable in KCC2 mutant mice, which suggests that KCC2 strongly modulates the excitability of spinal cord networks...

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..These results suggest that descending pathways, in particular serotonergic projections, control the strength of reciprocal inhibition and therefore shape the locomotor pattern in the neonatal rat...

..Interneuronal excitability is crucial for the activity-dependent development of spinal cord networks...

..Conversely, after SCI, BDNF upregulates KCC2 and restores RDD. Our results open new perspectives for the development of therapeutic strategies to alleviate spasticity...

..This study provides evidence that I(NaP) generates pacemaker activities in CPG interneurons and contributes to the regulation of the locomotor activity...

..Therefore influences from the brain stem may play an essential role in the maturation of inhibitory synaptic transmission, possibly by upregulating KCC2 and its functionality...

..Some neural controls are more clearly demonstrable in the developing animal preparation than in the adult because the latter exhibits an array of complex and redundant adaptive mechanisms...

..These data demonstrate that bicuculline-M may not reveal accurately the contribution of GABA(A) receptors in motor control and the intrinsic properties of disinhibited networks...

..We conclude that primary afferent fibers act as excitatory interneurons and that GABA, through PADs reaching firing threshold, is still playing a key role in promoting spontaneous activity in neonates...

..We concluded that gravity was critical to shape development of the supraspinal afferents in the lumbar spinal cord throughout the postnatal period...

..Our results raise the possibility that inhibitory synapses exert a facilitatory action on distant excitatory inputs and slight changes of E(Cl) may have important consequences for network processing...

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..To conclude, transneuronal tracing with RV, combined with an immunohistochemical detection of neuronal determinants, allows a very specific mapping of motor networks involved in the control of single muscles...

..Finally, improvements in the understanding of the mechanisms underlying spasticity may lead to new treatments of this disabling complication affecting patients with SCI...

..Taken together, the present results indicate that maturation of chloride homeostasis is not completed at birth in the rat and that the upregulation of KCC2 plays a key role in the shift from depolarizing to hyperpolarizing IPSPs...

..The two GABAB receptor antagonists, CGP 35348 and CGP 55845A blocked the effects of baclofen. These two compounds may be useful tools to study the evolution of GABAB receptor-mediated presynaptic inhibition during ontogenesis...

..These results demonstrate that 5-HT is critical in improving the locomotor-related alternations in the neonatal rat...

..Studies carried out on this preparation deal with three major areas: (1) relations between spontaneous activity and maturation of spinal network, (2) organisation of the different spinal networks, (3) key role of the descending pathways...

..These findings may have implications for therapeutic procedures, which should focus on the survival of the motoneuronal pool and/or the maintenance of functional neuro-muscular connexions to reduce motor impairments in humans...

..Different types of experiments (hypergravity, microgravity) are planned to test this hypothesis...

..These cells may, together with the rostral edge cells, be responsible for the locomotor-related modulation of activity in reticulospinal and vestibulospinal neurons...

..Glucose at its standard concentration appears to be an adequate ES for the neonatal spinal cord in vitro...