Neonatal capsaicin treatment alters the metabolic activity of subcortical somatosensory structures of developing rats in response to whisker stimulation.

Sprague-Dawley rats neonatally treated with capsaicin exhibited significant changes in 2-deoxy-glucose uptake in the subcortical somatosensory structures following repetitive whisker deflection. There was an increased uptake in the spinal trigeminal nucleus pars caudalis and a decrease in the principal sensory nucleus and the ventral posteromedial thalamic nucleus. The present study suggests that disruption of nociceptive afferents during development causes functional changes to subcortical somatosensory trigeminal nuclei.