Biomaterial Database

Multiple branching of cerebellar efferent projections in cats. 1978

D L Tolbert, and H Bantli, and J R Bloedel

The retrograde labeling of neurons in the deep cerebellar nuclei with horseradish peroxidase was used to compare the morphological characteristics of neurons in the dentate and interposed nuclei projecting in the cerebellothalamic, cerebello-olivary, and cerebellar nucleocortical pathways. The results from these studies demonstrated that cerebellothalamic and nucleocortical projections from the dentate and interposed nuclei originate from similar populations of spindle- and multipolar-shaped neurons with somal diameters throughout the range of cells present in the deep nuclei. However, only spindle-shaped neurons with somal diameters of 9--15 microns project in the cerebello-olivary pathway. From these anatomical studies, it was concluded that some of the neurons in the dentate and interposed nuclei which project to the thalamus, inferior olive, and cerebellar cortex have similar morphological characteristics. Electrophysiological experiments were carried out to investigate whether or not some of these neurons project to all three sites viaaxon collaterals. From stimulus sites in the thalamus, inferior olive, and cerebellar cortex, numerous neurons were antidromically activated in the cerebellar nuclei. Collision experiments between these antidromic responses confirmed that single neurons projected to all three of these sites. These studies therefore demonstrate that the axons of some neurons in the dentate and interposed nuclei have collateral branches in both the ascending and descending limbs of the brachium conjunctivum as well as in the cerebellar nucleocortical pathway. Functional implications of the collateral branching of cerebellar efferent projections are discussed.

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
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
D002525	Cerebellar Cortex	The superficial GRAY MATTER of the CEREBELLUM. It consists of two main layers, the stratum moleculare and the stratum granulosum.	Cortex Cerebelli,Cerebelli, Cortex,Cerebellus, Cortex,Cortex Cerebellus,Cortex, Cerebellar
D002531	Cerebellum	The part of brain that lies behind the BRAIN STEM in the posterior base of skull (CRANIAL FOSSA, POSTERIOR). It is also known as the "little brain" with convolutions similar to those of CEREBRAL CORTEX, inner white matter, and deep cerebellar nuclei. Its function is to coordinate voluntary movements, maintain balance, and learn motor skills.	Cerebella,Corpus Cerebelli,Parencephalon,Cerebellums,Parencephalons
D004525	Efferent Pathways	Nerve structures through which impulses are conducted from a nerve center toward a peripheral site. Such impulses are conducted via efferent neurons (NEURONS, EFFERENT), such as MOTOR NEURONS, autonomic neurons, and hypophyseal neurons.	Motor Pathways,Efferent Pathway,Pathway, Efferent,Pathways, Efferent
D006735	Horseradish Peroxidase	An enzyme isolated from horseradish which is able to act as an antigen. It is frequently used as a histochemical tracer for light and electron microscopy. Its antigenicity has permitted its use as a combined antigen and marker in experimental immunology.	Alpha-Peroxidase,Ferrihorseradish Peroxidase,Horseradish Peroxidase II,Horseradish Peroxidase III,Alpha Peroxidase,II, Horseradish Peroxidase,III, Horseradish Peroxidase,Peroxidase II, Horseradish,Peroxidase III, Horseradish,Peroxidase, Ferrihorseradish,Peroxidase, Horseradish
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
D013788	Thalamus	Paired bodies containing mostly GRAY MATTER and forming part of the lateral wall of the THIRD VENTRICLE of the brain.	Thalamencephalon,Thalamencephalons