TY - JOUR
T1 - Cardiovascular effects and c-Fos expression in the rat hindbrain in response to innocuous stomach distension
AU - Molinari, Claudio
AU - Sabbatini, Maurizio
AU - Grossini, Elena
AU - Mary, David A.S.G.
AU - Cannas, Mario
AU - Vacca, Giovanni
PY - 2006/3/31
Y1 - 2006/3/31
N2 - The present work was planned to study the effects of non-noxious gastric distension on hemodynamic variables and on cardiovascular hindbrain areas detected by means of c-Fos immunoreactivity, to determine the afferent and central mechanisms involved. In anesthetized rats, innocuous stomach distension increased arterial blood pressure and heart rate and induced c-Fos immunoreactivity within nucleus tractus solitarii, nucleus ambiguus, ventrolateral medulla and lateral reticular nucleus. Bilateral vagotomy abolished the pressor response and c-Fos immunoreactivity in nucleus ambiguus and ventrolateral medulla. Also, c-Fos immunoreactivity was significantly decreased in nucleus tractus solitarii and lateral reticular nucleus. After bilateral splanchnicotomy the pressor and tachycardic responses caused by gastric distension were reduced. c-Fos immunoreactivity in nucleus tractus solitarii, lateral reticular nucleus and nucleus ambiguus was reduced in comparison to the intact rats. In ventrolateral medulla a preferential localization of c-Fos immunoreactivity was found within its caudal portion. It was shown that such gastric distension, known to activate low threshold mechanoreceptors, induced cardiovascular effects via both vagal and splanchnic afferents and involving their central convergence and interaction in modulating the baroreceptor buffer system.
AB - The present work was planned to study the effects of non-noxious gastric distension on hemodynamic variables and on cardiovascular hindbrain areas detected by means of c-Fos immunoreactivity, to determine the afferent and central mechanisms involved. In anesthetized rats, innocuous stomach distension increased arterial blood pressure and heart rate and induced c-Fos immunoreactivity within nucleus tractus solitarii, nucleus ambiguus, ventrolateral medulla and lateral reticular nucleus. Bilateral vagotomy abolished the pressor response and c-Fos immunoreactivity in nucleus ambiguus and ventrolateral medulla. Also, c-Fos immunoreactivity was significantly decreased in nucleus tractus solitarii and lateral reticular nucleus. After bilateral splanchnicotomy the pressor and tachycardic responses caused by gastric distension were reduced. c-Fos immunoreactivity in nucleus tractus solitarii, lateral reticular nucleus and nucleus ambiguus was reduced in comparison to the intact rats. In ventrolateral medulla a preferential localization of c-Fos immunoreactivity was found within its caudal portion. It was shown that such gastric distension, known to activate low threshold mechanoreceptors, induced cardiovascular effects via both vagal and splanchnic afferents and involving their central convergence and interaction in modulating the baroreceptor buffer system.
KW - Arterial blood pressure
KW - Central cardiovascular control
KW - Heart rate
KW - Low threshold mechanoreceptors
KW - Splanchnic nerve
KW - Vagus nerve
UR - http://www.scopus.com/inward/record.url?scp=33644865667&partnerID=8YFLogxK
U2 - 10.1016/j.brainresbull.2005.11.014
DO - 10.1016/j.brainresbull.2005.11.014
M3 - Article
SN - 0361-9230
VL - 69
SP - 140
EP - 146
JO - Brain Research Bulletin
JF - Brain Research Bulletin
IS - 2
ER -