A study of the localization of the rabbit laryngeal and pharyngeal motoneurons by means of the retrograde cell-labelling technique.
| Project/Area Number |
59570765
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Morphological basic dentistry
|
|---|
| Research Institution | Osaka University |
|---|
Principal Investigator |
KITAMURA Seiichiro Osaka University Faculty of Dentistry, 歯学部, 助教授 (30093404)
|
|---|
| Project Period (FY) |
1984 – 1986
|
| Project Status |
Completed (Fiscal Year 1986)
|
| Budget Amount *help |
¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 1986: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1985: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1984: ¥1,100,000 (Direct Cost: ¥1,100,000)
|
|---|
| Keywords | Laryngeal muscles / Pharyngeal muscles / Motoneurons / Localization / Nucleus ambiguus / Vagus nerve / Bulbar accessory nerve / ウサギ |
|---|
| Research Abstract |
1. The laryngeal motoneurons.
(1) Origin cells of the superior laryngeal nerve are found in the rostral third of the nucleus ambiguus (NA) to be located in a cell group (CoG) formed by a compact arrangement of the smallest NA-neurons and also in a group (SGm) of slightly larger neurons scattered medial to CoG. Those of the inferior laryngeal nerve are located in a scattered group (DiG) of still larger neurons, occupying the caudal two-thirds of the nucleus.
(2) The motoneurons supplying the cricothyroid muscles, which is innervated by the superior laryngeal nerve and acts as a tensor for the vocal fold. are located in the SGm in the rostral third of NA. The motoneurons supplying the muscles innervated by the inferior laryngeal nerve are located in the DiG of the caudal two-thirds of NA, where they displayed a rostrocaudal myotopical arrangement in the order of posterior cricoarytenoid, playing a role of abductor for the vocal fold, and thyroarytenoid and then posterior cricoarytenoid. both playing that of adductors.
(3) Axons of the tensor and abductor laryngeal muscles traverse the vagal rootlets and then the vagal trunk to enter the superior and inferior laryngeal nerves, respectively. While those of the adductor muscles traverse the rootlets of the accessory cranial root and then reach the vagal trunk as the interal branch of the accessory nerve to enter the inferior laryngeal nerve.
2. The pharyngeal motoneurons.
Although the localization of these motoneurons and peripheral courses of their axons are now under study, it has been roughly known from our preliminary experiments that they display a different intra-NA distribution from that of the layngeal motoneurons, and that differences in the localization of somata and in the peripheral courses of axon are also found between the motoneurons supplying the pharyngeal costrictors and those supplying the pharyngeal elevators.
|
Report
(1 results)
Research Products
(12 results)
