Biomaterial Database

Light- and electron-microscopic localization of primary dental afferents to medullary dorsal horn (pars caudalis). 1986

M A Henry, and L E Westrum, and L R Johnson

Light-microscopic (LM) and ultrastructural (electron-microscopic, or EM) identification of primary dental afferents to medullary dorsal horn (MDH) was demonstrated in the cat following injections of horseradish peroxidase (HRP) into pulpal chambers of unilateral maxillary and mandibular posterior teeth, including the cuspids. Use of a new osmication protocol improved and simplified the EM localization of reaction product within the brain stem terminals. LM examination showed that the projection pattern varied between the different levels of MDH. At caudal levels, the labeling was primarily confined to a narrow band consisting of a dense projection to the dorsomedial portion of laminae I and superficial II and a less intense projection to lamina V. The pattern to rostral levels became increasingly more dense and extensive within these same laminae. LM examination of the tooth apex region showed that a limited spread to the periodontal ligament occurred in some cases. EM investigation of the ipsilateral MDH demonstrated reaction product in terminals with synaptic vesicles that are presynaptic to small and medium-sized dendrites. Labeled axonal endings in close association with cell bodies were also observed. No labeled structures were identified in the contralateral MDH. Some of the reaction product found with EM was below the LM limit of resolution, and thus ultrastructural investigation is necessary for a complete analysis of any pathway when using HRP.

UI	MeSH Term	Description	Entries
D008526	Medulla Oblongata	The lower portion of the BRAIN STEM. It is inferior to the PONS and anterior to the CEREBELLUM. Medulla oblongata serves as a relay station between the brain and the spinal cord, and contains centers for regulating respiratory, vasomotor, cardiac, and reflex activities.	Accessory Cuneate Nucleus,Ambiguous Nucleus,Arcuate Nucleus of the Medulla,Arcuate Nucleus-1,External Cuneate Nucleus,Lateral Cuneate Nucleus,Nucleus Ambiguus,Ambiguus, Nucleus,Arcuate Nucleus 1,Arcuate Nucleus-1s,Cuneate Nucleus, Accessory,Cuneate Nucleus, External,Cuneate Nucleus, Lateral,Medulla Oblongatas,Nucleus, Accessory Cuneate,Nucleus, Ambiguous,Nucleus, External Cuneate,Nucleus, Lateral Cuneate
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D009475	Neurons, Afferent	Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.	Afferent Neurons,Afferent Neuron,Neuron, Afferent
D010513	Periodontal Ligament	The fibrous CONNECTIVE TISSUE surrounding the TOOTH ROOT, separating it from and attaching it to the alveolar bone (ALVEOLAR PROCESS).	Alveolodental Ligament,Alveolodental Membrane,Gomphosis,Alveolodental Ligaments,Alveolodental Membranes,Gomphoses,Ligament, Alveolodental,Ligament, Periodontal,Membrane, Alveolodental,Periodontal Ligaments
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D003782	Dental Pulp	A richly vascularized and innervated connective tissue of mesodermal origin, contained in the central cavity of a tooth and delimited by the dentin, and having formative, nutritive, sensory, and protective functions. (Jablonski, Dictionary of Dentistry, 1992)	Dental Pulps,Pulp, Dental,Pulps, Dental
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012668	Trigeminal Ganglion	The semilunar-shaped ganglion containing the cells of origin of most of the sensory fibers of the trigeminal nerve. It is situated within the dural cleft on the cerebral surface of the petrous portion of the temporal bone and gives off the ophthalmic, maxillary, and part of the mandibular nerves.	Gasserian Ganglion,Semilunar Ganglion,Gasser's Ganglion,Trigeminal Ganglia,Ganglia, Trigeminal,Ganglion, Gasser's,Ganglion, Gasserian,Ganglion, Semilunar,Ganglion, Trigeminal,Gasser Ganglion,Gassers Ganglion,Semilunar Ganglions,Trigeminal Ganglias,Trigeminal Ganglions
D014276	Trigeminal Nerve	The 5th and largest cranial nerve. The trigeminal nerve is a mixed motor and sensory nerve. The larger sensory part forms the ophthalmic, mandibular, and maxillary nerves which carry afferents sensitive to external or internal stimuli from the skin, muscles, and joints of the face and mouth and from the teeth. Most of these fibers originate from cells of the TRIGEMINAL GANGLION and project to the TRIGEMINAL NUCLEUS of the brain stem. The smaller motor part arises from the brain stem trigeminal motor nucleus and innervates the muscles of mastication.	Cranial Nerve V,Fifth Cranial Nerve,Nerve V,Nervus Trigeminus,Cranial Nerve, Fifth,Fifth Cranial Nerves,Nerve V, Cranial,Nerve Vs,Nerve, Fifth Cranial,Nerve, Trigeminal,Trigeminal Nerves,Trigeminus, Nervus