Biomaterial Database

[An electron microscopic study of the origins of the projections of the first auditory area of the cortex (AI) to the medial geniculate body in cats]. 1990

Iu A Gonchar, and V I Kravets

An electron microscope study of retrogradely labelled neurons in layer VI of the primary auditory cortex (AI) after injection of the horseradish peroxidase to the medial geniculate body was carried out in cats. Three-eight synapses (4.6 +/- 0.6 at an average) were revealed on the somata profiles of these retrogradely labelled cortico-geniculate neurons. Synapses occupied 10.8 +/- 1.0% of the somatic profile of cortico-geniculate neurons. Almost all (98.7%) of these axosomatic synapses had symmetrical contacts and were formed by axonal terminals with small elongated synaptic vesicles. HRP retrogradely labelled axonal terminals of geniculo-cortical fibres were revealed in neuropil of layer VI. They contained large round synaptic vesicles and formed asymmetrical synapses, mainly on spines. The role of axo-somatic synapses in regulation of the activity of cortico-geniculate neurons was discussed.

UI	MeSH Term	Description	Entries
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
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
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
D003584	Cytological Techniques	Methods used to study CELLS.	Cytologic Technics,Cytological Technic,Cytological Technics,Cytological Technique,Technic, Cytological,Technics, Cytological,Technique, Cytological,Techniques, Cytological,Cytologic Technic,Technic, Cytologic,Technics, Cytologic
D005829	Geniculate Bodies	Part of the DIENCEPHALON inferior to the caudal end of the dorsal THALAMUS. Includes the lateral geniculate body which relays visual impulses from the OPTIC TRACT to the calcarine cortex, and the medial geniculate body which relays auditory impulses from the lateral lemniscus to the AUDITORY CORTEX.	Lateral Geniculate Body,Medial Geniculate Body,Metathalamus,Corpus Geniculatum Mediale,Geniculate Nucleus,Lateral Geniculate Nucleus,Medial Geniculate Complex,Medial Geniculate Nucleus,Nucleus Geniculatus Lateralis Dorsalis,Nucleus Geniculatus Lateralis Pars Dorsalis,Bodies, Geniculate,Complex, Medial Geniculate,Complices, Medial Geniculate,Corpus Geniculatum Mediales,Geniculate Bodies, Lateral,Geniculate Bodies, Medial,Geniculate Body,Geniculate Body, Lateral,Geniculate Body, Medial,Geniculate Complex, Medial,Geniculate Complices, Medial,Geniculate Nucleus, Lateral,Geniculate Nucleus, Medial,Geniculatum Mediale, Corpus,Geniculatum Mediales, Corpus,Lateral Geniculate Bodies,Medial Geniculate Bodies,Medial Geniculate Complices,Mediale, Corpus Geniculatum,Mediales, Corpus Geniculatum,Nucleus, Geniculate,Nucleus, Lateral Geniculate,Nucleus, Medial Geniculate
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
D001303	Auditory Cortex	The region of the cerebral cortex that receives the auditory radiation from the MEDIAL GENICULATE BODY.	Brodmann Area 41,Brodmann Area 42,Brodmann's Area 41,Heschl Gyrus,Heschl's Gyrus,Auditory Area,Heschl's Convolutions,Heschl's Gyri,Primary Auditory Cortex,Temporal Auditory Area,Transverse Temporal Gyri,Area 41, Brodmann,Area 41, Brodmann's,Area 42, Brodmann,Area, Auditory,Area, Temporal Auditory,Auditory Areas,Auditory Cortex, Primary,Brodmanns Area 41,Cortex, Auditory,Cortex, Primary Auditory,Gyrus, Heschl,Gyrus, Heschl's,Gyrus, Transverse Temporal,Heschl Convolutions,Heschl Gyri,Heschls Convolutions,Heschls Gyri,Heschls Gyrus,Primary Auditory Cortices,Temporal Auditory Areas,Temporal Gyrus, Transverse,Transverse Temporal Gyrus
D013569	Synapses	Specialized junctions at which a neuron communicates with a target cell. At classical synapses, a neuron's presynaptic terminal releases a chemical transmitter stored in synaptic vesicles which diffuses across a narrow synaptic cleft and activates receptors on the postsynaptic membrane of the target cell. The target may be a dendrite, cell body, or axon of another neuron, or a specialized region of a muscle or secretory cell. Neurons may also communicate via direct electrical coupling with ELECTRICAL SYNAPSES. Several other non-synaptic chemical or electric signal transmitting processes occur via extracellular mediated interactions.	Synapse