Nociceptive signaling in the periphery and spinal cord

Abstract Responses to painful or noxious stimuli are functional at birth. However, postnatal changes in the transmitters, receptors, and pathways involved in nociceptive signaling result in significant age-related changes in the nature and degree of response. Noxious mechanical, thermal, and chemical stimuli are detected by peripheral nociceptors, transduced into electrical stimuli, and transmitted to the spinal cord. Within the spinal cord, there are significant postnatal changes in the balance of inhibitory and excitatory signaling, that not only influence the acute response to afferent input, but can also underlie long-term alterations in sensory processing following tissue injury in early life. Evaluating age-related changes in nociceptive signaling is essential not only for understanding acute behavioral responses to noxious stimuli, but also for identifying the most appropriate and effective pain-management interventions at different developmental ages.