Differential activation of pontomedullary nuclei by acid perfusion of different regions of the esophagus. Brain Res 2010 Sep 17;1352:94-107
Date
07/27/2010Pubmed ID
20655885Pubmed Central ID
PMC2926140DOI
10.1016/j.brainres.2010.07.048Scopus ID
2-s2.0-77956172913 (requires institutional sign-in at Scopus site) 9 CitationsAbstract
The objective of this study was to determine the brain stem nuclei and physiological responses activated by esophageal acidification. The effects of perfusion of the cervical (ESOc), or thoracic (ESOt) esophagus with PBS or HCl on c-fos immunoreactivity of the brain stem or on physiological variables, and the effects of vagotomy were examined in anesthetized cats. We found that acidification of the ESOc increased the number of c-fos positive neurons in the area postrema (AP), vestibular nucleus (VN), parabrachial nucleus (PBN), nucleus ambiguus (NA), dorsal motor nucleus (DMN), and all subnuclei of the nucleus tractus solitarius (NTS), but one. Acidification of the ESOt activated neurons in the central (CE), caudal (CD), dorsomedial (DM), dorsolateral (DL), ventromedial (VM) subnuclei of NTS, and the DMN. Vagotomy blocked all c-fos responses to acid perfusion of the whole esophagus (ESOw). Perfusion of the ESOc or ESOt with PBS activated secondary peristalsis (2P), but had no effect on blood pressure, heart rate, or respiratory rate. Perfusion of the ESOc, but not ESOt, with HCl activated pharyngeal swallowing (PS), profuse salivation, or physiological correlates of emesis. Vagotomy blocked all physiological effects of ESOw perfusion. We conclude that acidification of the ESOc and ESOt activate different sets of pontomedullary nuclei and different physiological responses. The NTSce, NTScom, NTSdm, and DMN are associated with activation of 2P, the NTSim and NTSis, are associated with activation of PS, and the AP, VN, and PBN are associated with activation of emesis and perhaps nausea. All responses to esophageal fluid perfusion or acidification are mediated by the vagus nerves.
Author List
Lang IM, Medda BK, Shaker RAuthors
Ivan M. Lang DVM, PhD Adjunct Professor in the Medicine department at Medical College of WisconsinBidyut K. Medda PhD Associate Professor in the Medicine department at Medical College of Wisconsin
Reza Shaker MD Assoc Provost, Sr Assoc Dean, Ctr Dir, Chief, Prof in the Medicine department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
AnimalsCats
Esophagus
Femoral Artery
Heart Rate
Humans
Medulla Oblongata
Perfusion
Peristalsis
Pons
Pyramidal Tracts
Species Specificity
Spinal Cord
Vagotomy