Gene Expression and Signaling Pathways by Extracellular Acidification
The respiratory response to extracellular acidosis by hypercapnia is mediated by central chemoreceptor neurons in the medulla oblongata . There are actually two defined groups of respiratory neurons. The dorsal group of neurons is located in and near the nucleus of the tractus solitarius and their activity is regulated by changes in the arterial partial pressure of CO2 (Pco2), O2 (Po2) or H+. The ventral group is a long column of neurons that extends through the nucleus ambiguous and retroambiguous in the ventrolateral medulla. In addition to reacting to peripheral stimuli, the ventral neurons detect changes in the H+ and/or CO2 concentrations in the cerebrospinal fluid (CSF) and brain interstitial fluid . The capacity to detect these changes is called central chemosensitivity.
KeywordsExtracellular Acidification Dorsal Root Ganglion Cell Respiratory Regulation Extracellular Acidosis Brain Interstitial Fluid
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