Responses of neurons in the caudal medullary lateral tegmental field to visceral inputs and vestibular stimulation in vertical planes. Am J Physiol Regul Integr Comp Physiol 2012 Nov 01;303(9):R929-40
Date
09/08/2012Pubmed ID
22955058Pubmed Central ID
PMC3517700DOI
10.1152/ajpregu.00356.2012Scopus ID
2-s2.0-84868379223 (requires institutional sign-in at Scopus site) 14 CitationsAbstract
The dorsolateral reticular formation of the caudal medulla, or the lateral tegmental field (LTF), has been classified as the brain's "vomiting center", as well as an important region in regulating sympathetic outflow. We examined the responses of LTF neurons in cats to rotations of the body that activate vestibular receptors, as well as to stimulation of baroreceptors (through mechanical stretch of the carotid sinus) and gastrointestinal receptors (through the intragastric administration of the emetic compound copper sulfate). Approximately half of the LTF neurons exhibited graviceptive responses to vestibular stimulation, similar to primary afferents innervating otolith organs. The other half of the neurons had complex responses, including spatiotemporal convergence behavior, suggesting that they received convergent inputs from a variety of vestibular receptors. Neurons that received gastrointestinal and baroreceptor inputs had similar complex responses to vestibular stimulation; such responses are expected for neurons that contribute to the generation of motion sickness. LTF units with convergent baroreceptor and vestibular inputs may participate in producing the cardiovascular system components of motion sickness, such as the changes in skin blood flow that result in pallor. The administration of copper sulfate often modulated the gain of responses of LTF neurons to vestibular stimulation, particularly for units whose spontaneous firing rate was altered by infusion of drug (median of 459%). The present results raise the prospect that emetic signals from the gastrointestinal tract modify the processing of vestibular inputs by LTF neurons, thereby affecting the probability that vomiting will occur as a consequence of motion sickness.
Author List
Moy JD, Miller DJ, Catanzaro MF, Boyle BM, Ogburn SW, Cotter LA, Yates BJ, McCall AAAuthor
Jennifer D. Bruening MD Assistant Professor in the Otolaryngology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsCats
Emetics
Male
Medulla Oblongata
Models, Animal
Motion Sickness
Neurons
Orientation
Pressoreceptors
Semicircular Canals
Stress, Mechanical
Vestibule, Labyrinth
Viscera
Vomiting
