Chronic Oral Capsaicin Exposure During Development Leads to Adult Rats with Reduced Taste Bud Volumes

Introduction A cross-sensory interaction between gustatory and trigeminal nerves occurs in the anterior tongue. Surgical manipulations have demonstrated that the strength of this relationship varies across development. Capsaicin is a neurotoxin that affects fibers of the somatosensory lingual nerve surrounding taste buds, but not fibers of the gustatory chorda tympani nerve which synapse with taste receptor cells. Since capsaicin is commonly consumed by many species, including humans, the experimental use of this neurotoxin provides a naturalistic perturbation of the lingual trigeminal system. Neonatal or adult rats consumed oral capsaicin for 40 days, and we examined the cross-sensory effect on the morphology of taste buds across development.