Biomaterial Database

Ultrastructure of contralaterally projecting vestibular efferent neurons in the cat. 1988

M J Parker, and M J Lyon, and R R Gacek

Department of Otolaryngology and Communication Sciences, State University of New York-Health Science Center, Syracuse 13210.

Numerous reports have demonstrated that primary vestibular afferent axons terminate in the vicinity of centrally located vestibular efferent (VE) neurons. The goal of this study was to morphologically demonstrate contact of primary vestibular afferents directly on the soma of contralaterally projecting VE neurons, as well as develop a quantitative description of these neurons. A right vestibular neurectomy was performed in three young adult cats followed up three days later by the placement of horseradish peroxidase into the left vestibule. Labeled contralateral (right) VE neurons were examined in a transmission electron microscope for degenerating synaptic profiles contacting the soma. Ultrastructural characteristics of VE neurons, including nuclear size, volume fraction of intracellular organelles, number of synaptic profiles, and cellular shape, were quantitatively analyzed. No degenerating synaptic profiles were observed on labeled VE soma, although degenerating axons were present nearby. Statistical analysis of volume fraction data of the VE neurons suggests a continuum of a single subpopulation of cells rather than multiple subpopulations.

UI	MeSH Term	Description	Entries
D009476	Neurons, Efferent	Neurons which send impulses peripherally to activate muscles or secretory cells.	Efferent Neurons,Efferent Neuron,Neuron, Efferent
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
D002467	Cell Nucleus	Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Cell Nuclei,Nuclei, Cell,Nucleus, Cell
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
D001306	Auditory Pathways	NEURAL PATHWAYS and connections within the CENTRAL NERVOUS SYSTEM, beginning at the hair cells of the ORGAN OF CORTI, continuing along the eighth cranial nerve, and terminating at the AUDITORY CORTEX.	Auditory Pathway,Pathway, Auditory,Pathways, Auditory
D001369	Axons	Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.	Axon
D014726	Vestibular Nuclei	The four cellular masses in the floor of the fourth ventricle giving rise to a widely dispersed special sensory system. Included is the superior, medial, inferior, and LATERAL VESTIBULAR NUCLEUS. (From Dorland, 27th ed)	Schwalbe Nucleus,Vestibular Nucleus, Medial,Schwalbe's Nucleus,Medial Vestibular Nucleus,Nuclei, Vestibular,Nucleus, Medial Vestibular,Nucleus, Schwalbe,Nucleus, Schwalbe's,Schwalbes Nucleus