Abstract
Cobaltic-lysine complex was used to label the afferent and efferent components of the glossopharyngeal nerve in the ganglion and brainstem of the Mexican salamander, axolotl (Ambystoma mexicanum). The distribution of afferent cell bodies in the combined glossopharyngeal-vagus ganglion (the IX-X ganglion) was reconstructed from serial sections, and the sizes of the cell bodies were measured. The central projection of afferents and the location of efferent cell bodies were determined by the tracer. The afferent cell bodies in the ganglion were medium-sized (ca. 25 μm). Cell bodies with a single process were seen. The ganglion was not clearly divided into superior and inferior ganglia, as is observed in mammals and frogs, but comprised a single ganglion. Labelled cells were diffusely distributed in the rostral part of the IX-X ganglion. A few labelled cells also were seen in the caudal part, where the vagus nerve fibers and cell bodies were mainly distributed. Double labellings of the glossopharyngeal and vagus nerves with HRP and cobaltic-lysine demonstrated that the ganglion cells of each nerve are not clearly separated in the IX-X ganglion. In the brainstem, the majority of afferent fibers formed thick ascending and descending limbs in the solitary fasciculus. The remaining afferent fibers formed a thin bundle in the spinal tract of the trigeminal nerve, which had a short ascending limb and a long descending limb. These two bundles had terminal areas in the ipsilateral brainstem: in the dorsal gray matter for the solitary fasciculus and in the lateral funiculus for the spinal tract of the trigeminal nerve, respectively. The cell bodies of the efferent neurons possessed developed dendritic arborizations in the ventrolateral white matter, and formed a longitudinal cell column in the ventrolateral margin of the gray matter. Thus, the glossopharyngeal nerve system in the axolotl assumes a primordial form in its ganglions, but its topographical organization in the brainstem is basically similar to that in anurans.
| Original language | English |
|---|---|
| Pages (from-to) | 473-484 |
| Number of pages | 12 |
| Journal | Journal of Comparative Neurology |
| Volume | 302 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 1990 |
| Externally published | Yes |
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Keywords
- Ambystoma
- brainstem
- chemoreceptors
- neuroanatomy
- taste
ASJC Scopus subject areas
- Neuroscience(all)
Cite this
Morphology and distribution of the glossopharyngeal nerve afferent and efferent neurons in the Mexican salamander, axolotl : A cobaltic-lysine study. / Nagai, T.; Matsushima, T.
In: Journal of Comparative Neurology, Vol. 302, No. 3, 1990, p. 473-484.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Morphology and distribution of the glossopharyngeal nerve afferent and efferent neurons in the Mexican salamander, axolotl
T2 - A cobaltic-lysine study
AU - Nagai, T.
AU - Matsushima, T.
PY - 1990
Y1 - 1990
N2 - Cobaltic-lysine complex was used to label the afferent and efferent components of the glossopharyngeal nerve in the ganglion and brainstem of the Mexican salamander, axolotl (Ambystoma mexicanum). The distribution of afferent cell bodies in the combined glossopharyngeal-vagus ganglion (the IX-X ganglion) was reconstructed from serial sections, and the sizes of the cell bodies were measured. The central projection of afferents and the location of efferent cell bodies were determined by the tracer. The afferent cell bodies in the ganglion were medium-sized (ca. 25 μm). Cell bodies with a single process were seen. The ganglion was not clearly divided into superior and inferior ganglia, as is observed in mammals and frogs, but comprised a single ganglion. Labelled cells were diffusely distributed in the rostral part of the IX-X ganglion. A few labelled cells also were seen in the caudal part, where the vagus nerve fibers and cell bodies were mainly distributed. Double labellings of the glossopharyngeal and vagus nerves with HRP and cobaltic-lysine demonstrated that the ganglion cells of each nerve are not clearly separated in the IX-X ganglion. In the brainstem, the majority of afferent fibers formed thick ascending and descending limbs in the solitary fasciculus. The remaining afferent fibers formed a thin bundle in the spinal tract of the trigeminal nerve, which had a short ascending limb and a long descending limb. These two bundles had terminal areas in the ipsilateral brainstem: in the dorsal gray matter for the solitary fasciculus and in the lateral funiculus for the spinal tract of the trigeminal nerve, respectively. The cell bodies of the efferent neurons possessed developed dendritic arborizations in the ventrolateral white matter, and formed a longitudinal cell column in the ventrolateral margin of the gray matter. Thus, the glossopharyngeal nerve system in the axolotl assumes a primordial form in its ganglions, but its topographical organization in the brainstem is basically similar to that in anurans.
AB - Cobaltic-lysine complex was used to label the afferent and efferent components of the glossopharyngeal nerve in the ganglion and brainstem of the Mexican salamander, axolotl (Ambystoma mexicanum). The distribution of afferent cell bodies in the combined glossopharyngeal-vagus ganglion (the IX-X ganglion) was reconstructed from serial sections, and the sizes of the cell bodies were measured. The central projection of afferents and the location of efferent cell bodies were determined by the tracer. The afferent cell bodies in the ganglion were medium-sized (ca. 25 μm). Cell bodies with a single process were seen. The ganglion was not clearly divided into superior and inferior ganglia, as is observed in mammals and frogs, but comprised a single ganglion. Labelled cells were diffusely distributed in the rostral part of the IX-X ganglion. A few labelled cells also were seen in the caudal part, where the vagus nerve fibers and cell bodies were mainly distributed. Double labellings of the glossopharyngeal and vagus nerves with HRP and cobaltic-lysine demonstrated that the ganglion cells of each nerve are not clearly separated in the IX-X ganglion. In the brainstem, the majority of afferent fibers formed thick ascending and descending limbs in the solitary fasciculus. The remaining afferent fibers formed a thin bundle in the spinal tract of the trigeminal nerve, which had a short ascending limb and a long descending limb. These two bundles had terminal areas in the ipsilateral brainstem: in the dorsal gray matter for the solitary fasciculus and in the lateral funiculus for the spinal tract of the trigeminal nerve, respectively. The cell bodies of the efferent neurons possessed developed dendritic arborizations in the ventrolateral white matter, and formed a longitudinal cell column in the ventrolateral margin of the gray matter. Thus, the glossopharyngeal nerve system in the axolotl assumes a primordial form in its ganglions, but its topographical organization in the brainstem is basically similar to that in anurans.
KW - Ambystoma
KW - brainstem
KW - chemoreceptors
KW - neuroanatomy
KW - taste
UR - http://www.scopus.com/inward/record.url?scp=0025650267&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0025650267&partnerID=8YFLogxK
U2 - 10.1002/cne.903020305
DO - 10.1002/cne.903020305
M3 - Article
C2 - 1702112
AN - SCOPUS:0025650267
VL - 302
SP - 473
EP - 484
JO - Journal of Comparative Neurology
JF - Journal of Comparative Neurology
SN - 0021-9967
IS - 3
ER -