Presynaptic inhibition in the vertebrate spinal cord revisited.

摘要: The present review examines the experimental evidence supporting existence of central mechanisms able to modulate synaptic effectiveness sensory fibers ending in spinal cord vertebrates. first section covers work on mode operation and presynaptic inhibition, particular control involving axo-axonic synapses made by GABAergic interneurons with terminal arborizations afferent fibers. This includes reviewing ionic involved generation primary depolarization (PAD) synapses, ultrastructural basis underlying PAD, relationship between PAD conduction action potentials fibers, modeling inhibitory synapse. second deals functional organization inhibition. segmental descending group-I group-II muscle afferents, dealing local character as well differential inhibition selected collaterals individual muscle-spindle afferents cutaneous inputs. also observations modulation large including thin myelinated unmyelinated visceral actions tract neurons. third changes occurring during sleep fictive locomotion higher vertebrates humans execution a variety voluntary movements. In final section, we examine non-synaptic transmitter release, possibility that intraspinal endings release colocalized peptides similar way periphery. outcome studies presently reviewed is terminals are not hard-wired conductors information generated their peripheral receptors, but dynamic systems convey can be selectively addressed specific neuronal targets. flow appears play an important role integrated movements processing information, nociceptive information.