Abstract
We tested the hypothesis that application of the subunit B of cholera toxin (CTB) to the airway mucosa would produce labeling of neuronal somata and sensory fibers in the medulla oblongata. Using 125I-CTB as a tracer, we demonstrated first that CTB is transported across the tracheal epithelium, but once in the airway wall, it remains confined to the subepithelial space and lamina propria. Despite the rarity of intrinsic neurons in these areas, intraluminal CTB labeled ≈ 10-60 neurons/rat in the nucleus ambiguus and a smaller number of neurons in the dorsal motor nucleus of the vagus. Well-defined sensory fiber terminals were also labeled in the commissural, medial, and ventrolateral subnuclei of the nucleus of the tractus solitarius. Approximately 50 and 90% of the neurons labeled by intraluminal CTB were also labeled by injections of FluoroGold into the tracheal adventitia and lung parenchyma, respectively. These findings demonstrate that a substantial number of medullary vagal motoneurons innervate targets in the vicinity of the airway epithelium. These neurons do not appear to be segregated anatomically from vagal motoneurons that project to deeper layers of the airway wall or lung parenchyma.
| Original language | English (US) |
|---|---|
| Journal | American Journal of Physiology - Lung Cellular and Molecular Physiology |
| Volume | 280 |
| Issue number | 1 24-1 |
| State | Published - Jan 2001 |
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Keywords
- Airway epithelium
- Airway ganglia
- Parasympathetic system
- Retrograde neuronal markers
ASJC Scopus subject areas
- Pulmonary and Respiratory Medicine
- Cell Biology
- Physiology
- Physiology (medical)
Cite this
Labeling of vagal motoneurons and central afferents after injection of cholera toxin B into the airway lumen. / Fontán, J. Julio Pérez; Velloff, Christine R.
In: American Journal of Physiology - Lung Cellular and Molecular Physiology, Vol. 280, No. 1 24-1, 01.2001.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Labeling of vagal motoneurons and central afferents after injection of cholera toxin B into the airway lumen
AU - Fontán, J. Julio Pérez
AU - Velloff, Christine R.
PY - 2001/1
Y1 - 2001/1
N2 - We tested the hypothesis that application of the subunit B of cholera toxin (CTB) to the airway mucosa would produce labeling of neuronal somata and sensory fibers in the medulla oblongata. Using 125I-CTB as a tracer, we demonstrated first that CTB is transported across the tracheal epithelium, but once in the airway wall, it remains confined to the subepithelial space and lamina propria. Despite the rarity of intrinsic neurons in these areas, intraluminal CTB labeled ≈ 10-60 neurons/rat in the nucleus ambiguus and a smaller number of neurons in the dorsal motor nucleus of the vagus. Well-defined sensory fiber terminals were also labeled in the commissural, medial, and ventrolateral subnuclei of the nucleus of the tractus solitarius. Approximately 50 and 90% of the neurons labeled by intraluminal CTB were also labeled by injections of FluoroGold into the tracheal adventitia and lung parenchyma, respectively. These findings demonstrate that a substantial number of medullary vagal motoneurons innervate targets in the vicinity of the airway epithelium. These neurons do not appear to be segregated anatomically from vagal motoneurons that project to deeper layers of the airway wall or lung parenchyma.
AB - We tested the hypothesis that application of the subunit B of cholera toxin (CTB) to the airway mucosa would produce labeling of neuronal somata and sensory fibers in the medulla oblongata. Using 125I-CTB as a tracer, we demonstrated first that CTB is transported across the tracheal epithelium, but once in the airway wall, it remains confined to the subepithelial space and lamina propria. Despite the rarity of intrinsic neurons in these areas, intraluminal CTB labeled ≈ 10-60 neurons/rat in the nucleus ambiguus and a smaller number of neurons in the dorsal motor nucleus of the vagus. Well-defined sensory fiber terminals were also labeled in the commissural, medial, and ventrolateral subnuclei of the nucleus of the tractus solitarius. Approximately 50 and 90% of the neurons labeled by intraluminal CTB were also labeled by injections of FluoroGold into the tracheal adventitia and lung parenchyma, respectively. These findings demonstrate that a substantial number of medullary vagal motoneurons innervate targets in the vicinity of the airway epithelium. These neurons do not appear to be segregated anatomically from vagal motoneurons that project to deeper layers of the airway wall or lung parenchyma.
KW - Airway epithelium
KW - Airway ganglia
KW - Parasympathetic system
KW - Retrograde neuronal markers
UR - http://www.scopus.com/inward/record.url?scp=0342468058&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0342468058&partnerID=8YFLogxK
M3 - Article
VL - 280
JO - American Journal of Physiology - Heart and Circulatory Physiology
JF - American Journal of Physiology - Heart and Circulatory Physiology
SN - 0363-6135
IS - 1 24-1
ER -