Divergent neuroendocrine responses to localized and systemic inflammation.
The sympathetic nervous system (SNS) is part of an integrative network that functions to restore homeostasis following injury and infection. The SNS can provide negative feedback control over inflammation through the secretion of catecholamines from postganglionic sympathetic neurons and adrenal chromaffin cells (ACCs). Central autonomic structures receive information regarding the inflammatory status of the body and reflexively modulate SNS activity. However, inflammation and infection can also directly regulate SNS function by peripheral actions on postganglionic cells. The present review discusses how inflammation activates autonomic reflex pathways and compares the effect of localized and systemic inflammation on ACCs and postganglionic sympathetic neurons. Systemic inflammation significantly enhanced catecholamine secretion through an increase in Ca(2+) release from the endoplasmic reticulum. In contrast, acute and chronic GI inflammation reduced voltage-gated Ca(2+) current. Thus it appears that the mechanisms underlying the effects of peripheral and systemic inflammation neuroendocrine function converge on the modulation of intracellular Ca(2+) signaling.
Department of Biological Sciences, Brock University, St. Catharines, Ontario, Canada.
Mark K
MK
Lukewich
Laboratory for Autonomic Neuroscience, Pennington Biomedical Research Center, Baton Rouge, LA, USA.
Richard C
RC
Rogers
Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada; Department of Medicine, Queen's University, Kingston, Ontario, Canada. Electronic address: lomaxa@queensu.ca.
Alan E
AE
Lomax
D000818:Animals; D002118:Calcium / Q000276:immunology / Q000378:metabolism*; D020013:Calcium Signaling; D002395:Catecholamines / Q000276:immunology / Q000378:metabolism*; D019439:Chromaffin Cells / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D016207:Cytokines / Q000235:genetics / Q000276:immunology; D025461:Feedback, Physiological; D005786:Gene Expression Regulation; D006801:Humans; D007249:Inflammation / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D015212:Inflammatory Bowel Diseases / Q000235:genetics / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D009474:Neurons / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D018805:Sepsis / Q000235:genetics / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D013564:Sympathetic Nervous System / Q000276:immunology / Q000378:metabolism* / Q000473:pathology
D002395:Catecholamines; D016207:Cytokines; D002118:Calcium
Excitation secretion coupling; Inflammatory bowel disease; Neuroimmunology; Sepsis; Sympathetic nervous system