| dc.contributor.author | Saxon, Dale William. | en_US |
| dc.date.accessioned | 2014-10-21T12:37:18Z | |
| dc.date.available | 1992 | |
| dc.date.issued | 1992 | en_US |
| dc.identifier.other | AAINN80168 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10222/55334 | |
| dc.description | This thesis provides a comprehensive light and electron microscopic analysis of the ultrastructure of two subnuclei of the nucleus of the tractus solitarius (NTS) (i.e., subnucleus centralis and subnucleus interstitialis) and the paratrigeminal nucleus (PTN). In addition, the synaptology of primary afferents originating in the upper alimentary and respiratory tracts and terminating in these areas was investigated. The efferent connectivity and collateral organization of PTN neurons to regions of the medulla oblongata, pons and thalamus was elucidated. | en_US |
| dc.description | The transganglionic transport of horseradish peroxidase conjugated to wheat-germ agglutinin or cholera-toxin ($\beta$-subunit) was utilized to label anterogradely afferent terminals in the NTS and PTN which originated in the esophagus, pharynx and larynx. The esophagus has projections to the subnucleus centralis of the NTS, while the pharynx and larynx project to the subnucleus interstitialis of the NTS and PTN. Regardless of the viscus of origin, primary afferents terminating in the NTS and PTN were all found to have similar synaptic morphology. Anterogradely labeled primary afferent terminals all contained round, agranular vesicles and formed asymmetric synaptic contacts (RA) with small diameter dendrites. A second type of synaptic terminal containing pleomorphic, agranular vesicles and forming symmetric synaptic contacts (PS) did not contain HRP reaction product. Complex synaptic arrangements involving axon terminals, dendrites and dendrites containing vesicles were encountered in the NTSis and PTN but not the NTScen. | en_US |
| dc.description | The efferent connectivity and collateral organization of the PTN was elucidated in a series of fluorescent anterograde and retrograde tracing experiments. The PTN was found to have a diverse array of efferent projection sites including the contralateral PTN and thalamus and the NTS and parabrachial nucleus, bilaterally. Retrograde double-labeling experiments indicated that the PTN was highly collateralized to several of these sites and as such may have a general role in the modulation of these regions in response to primary afferent input received in the PTN. | en_US |
| dc.description | Thesis (Ph.D.)--Dalhousie University (Canada), 1992. | en_US |
| dc.language | eng | en_US |
| dc.publisher | Dalhousie University | en_US |
| dc.publisher | | en_US |
| dc.subject | Biology, Anatomy. | en_US |
| dc.subject | Biology, Neuroscience. | en_US |
| dc.title | Innervation of the upper alimentary and respiratory tracts: A light and electron microscopic study of the medulla oblongata of the rat. | en_US |
| dc.type | text | en_US |
| dc.contributor.degree | Ph.D. | en_US |
