Biomaterial Database

Morphogenesis and morphology of the brain stem nuclei of Cetacea. I. The hypoglossal nucleus. 1977

J Jansen, and H Korneliussen

1. The hypoglossal nucleus of whalebone whales is composed of four major subdivisions, forming four parallel columns, here called the dorsomedial, the dorsolateral, the ventromedial and the ventrolateral XII columns. 2. The ventromedial XII column extends throughout the hypoglossal nucleus, forming in whalebone whales the rostral as well as the caudal end of the nucleus. 3. The ventrolateral XII column is lamelliformed and splits into a dorsomedial and a ventrolateral part, the former intimately related topographically to the dorsomedial column. 4. The dorsomedial XII column is torpedo-shaped, tapering in rostral direction and terminating a little short of the rostral end of the ventromedial XII column, while the blunt end terminates immediately caudal to the obex. 5. The dorsolateral XII column is the shortest subdivision, approximately one fourth of the length of the entire hypoglossal nucleus. The blunt rostral end of the torpedo-shaped column blends with the dorsomedial XII column, its tapering caudal end terminating rostral to the obex. 6. The cells of the hypoglossal nucleus vary in size from small to medium-sized and large, the small ones dominating in the dorsomedial, the large ones in the dorsolateral and ventromedial XII columns. The ventrolateral column is characterized by spindle-shaped cells. 7. In the toothed whale Phocaena communis the differentiation of the hypoglossal nucleus is less clearcut than in whalebone whales, but a similar structural priniciple is recognizable.

UI	MeSH Term	Description	Entries
D007002	Hypoglossal Nerve	The 12th cranial nerve. The hypoglossal nerve originates in the hypoglossal nucleus of the medulla and supplies motor innervation to all of the muscles of the tongue except the palatoglossus (which is supplied by the vagus). This nerve also contains proprioceptive afferents from the tongue muscles.	Cranial Nerve XII,Twelfth Cranial Nerve,Nerve XII,Nervus Hypoglossus,Cranial Nerve XIIs,Cranial Nerve, Twelfth,Cranial Nerves, Twelfth,Hypoglossal Nerves,Hypoglossus, Nervus,Nerve XII, Cranial,Nerve XIIs,Nerve XIIs, Cranial,Nerve, Hypoglossal,Nerve, Twelfth Cranial,Nerves, Hypoglossal,Nerves, Twelfth Cranial,Twelfth Cranial Nerves,XII, Nerve,XIIs, Nerve
D001933	Brain Stem	The part of the brain that connects the CEREBRAL HEMISPHERES with the SPINAL CORD. It consists of the MESENCEPHALON; PONS; and MEDULLA OBLONGATA.	Brainstem,Truncus Cerebri,Brain Stems,Brainstems,Cerebri, Truncus,Cerebrus, Truncus,Truncus Cerebrus
D002591	Cetacea	An order of wholly aquatic MAMMALS occurring in all the OCEANS and adjoining seas of the world, as well as in certain river systems. They feed generally on FISHES, cephalopods, and crustaceans. Most are gregarious and most have a relatively long period of parental care and maturation. Included are DOLPHINS; PORPOISES; and WHALES. (From Walker's Mammals of the World, 5th ed, pp969-70)	Cetaceas
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
D013045	Species Specificity	The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.	Species Specificities,Specificities, Species,Specificity, Species