Postnatal development, electrophysiology, and sensory sural nerves

The sural sensory nerve, which innervates the lower extremities, is a useful model for studying the structural and functional characteristics of peripheral sensory nerves. Its development and myelination extends across the early postnatal through to the juvenile stage. Myelination of the sural nerve depends on interactions between axons and Schwann cells and requires a variety of factors including hormones, neurotrophic factors, nerve impulses, and transcription factors. Maternal deprivation or malnutrition during early life reduces the thickness of myelin and decreases the area and amplitude of the compound action potential of the sural nerve. Importantly, the replacement of tactile or social stimuli during experimental maternal isolation in rats prevents such effects. Electrical stimulation or neurotrophic factors favor the remyelination and regeneration of nerves damaged by crushing or neuropathies derived from genetic, infectious, or metabolic diseases such as diabetes mellitus.