Dual Control of Central Pattern Generators: Neonatal Rat Spinal Cord In Vitro
Neuromodulatory control of the spinal network generating locomotor activity has been studied using an in vitro preparation of isolated brain stem/spinal cord. The activity produced in these conditions consists (locomotor-like activity) in alternating bursts of action potentials between the right and left side and between flexor and extensor which can be recorded in the ventral roots. Comparison with in vivo data shows that at birth the newborn rat can perform locomotor movements with a period and phase relationships comparable to that recorded in vitro (i.e. close to 1s). The locomotor-like activity can be induced by serotonin and excitatory amino-acids. In contrast GABA can suppress all rhythmic activity. It is suggested that the overall activity of the spinal network result from a fine interaction of these various transmitter systems.
KeywordsRhythmic Activity Motor Pattern Central Pattern Generator Lumbar Spinal Cord Ventral Root
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