CO2-inhibited neurons in the medullary raphé are GABAergic.
Respir Physiol Neurobiol
; 203: 28-34, 2014 Nov 01.
Article
in En
| MEDLINE
| ID: mdl-25087734
ABSTRACT
Previous studies have reported subsets of medullary raphé neurons that are either stimulated or inhibited by CO2/pH in vitro, in situ, and in vivo. We tested the hypothesis that medullary raphé CO2-inhibited neurons are GABAergic. Extracellular recordings in unanesthetized juvenile in situ rat preparations showed reversible hypercapnia-induced suppression of 19% (63/323) of medullary raphé neurons, and this suppression persisted after antagonism of NMDA, AMPA/kainate, and GABAA receptors. We stained a subset of CO2-inhibited cells and found that most (11/12) had glutamic acid decarboxylase 67 immunoreactivity (GAD67-ir). These data indicate that the majority of acidosis-inhibited medullary raphé neurons are GABAergic, and that their chemosensitivity is independent of major fast synaptic inputs. Thus, CO2-sensitive GABAergic neurons may play a role in central CO2/pH chemoreception.
Key words
Full text:
1
Database:
MEDLINE
Main subject:
Carbon Dioxide
/
GABAergic Neurons
/
Midbrain Raphe Nuclei
/
Gamma-Aminobutyric Acid
Limits:
Animals
Language:
En
Year:
2014
Type:
Article