substantia nigra

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Related to Nigral: basal ganglia, Lewy bodies, Locus coeruleus, Nigrostriatal pathway

substantia

 [sub-stan´she-ah] (L.)
substance; used in anatomic nomenclature in naming various components of body tissues or structures.
substantia al´ba white matter.
substantia gelatino´sa the substance sheathing the posterior horn of the spinal cord and lining its central canal.
substantia gri´sea gray matter.
substantia ni´gra a dark layer of gray matter separating the tegmentum of the midbrain from the crus cerebri.

sub·stan·ti·a ni'g·ra

[TA]
a large cell mass, crescentic on transverse section, extending forward over the inner surface of the crus cerebri from the rostral border of the pons into the subthalamic region. It is composed of a dorsal stratum of closely spaced pigmented (that is, melanin-containing) cells, the pars compacta [TA]; a larger ventral region of widely scattered cells, the pars reticulata [TA]; and smaller less distinct regions, the pars lateralis [TA] and pars retrorubralis [TA]; the pars compacta in particular includes numerous cells that project forward to the striatum (caudate nucleus and putamen) and contain dopamine, which acts as the transmitter at their synaptic endings. Other, apparently nondopaminergic, cells of the substantia nigra project to a rostral part of the ventral nucleus of thalamus, to the middle layers of the superior colliculus, and to restricted parts of the reticular formation of the midbrain. The nigrostriatal projection is reciprocated by a massive striatonigral fiber system with multiple neurotransmitters, chief among which is γ-aminobutyric acid (GABA). The substantia nigra receives smaller afferent projections from the subthalamic nucleus, the lateral segment of the globus pallidus, the dorsal nucleus of the raphe, and the pedunculopontine nucleus of the midbrain. The pars reticulata forms part of the output system for the striate body. The substantia n. is involved in the metabolic disturbances associated with Parkinson disease and Huntington disease.

substantia nigra

(nī′grə, nĭg′rə)
n.
A layer of large pigmented nerve cells in the midbrain that produce dopamine and whose destruction is associated with Parkinson's disease.

substantia nigra

Etymology: L, substantia, essence, niger, black
a dark band of gray matter lying between the tegmentum of the midbrain and the crus cerebri.

sub·stan·ti·a nigra

(sŭb-stan'shē-ă nī'gră) [TA]
A large cell mass, crescentic on transverse section, extending forward over the dorsal surface of the crus cerebri from the rostral border of the pons into the subthalamic region; it is composed of a dorsal stratum of closely spaced pigmented (i.e., melanin-containing) cells, the pars compacta, and a larger ventral region of widely scattered cells, the pars reticulata. The substantia nigra is involved in the metabolic disturbances associated with parkinsonism and Huntington disease.

substantia nigra

A layer of grey matter (nerve cell bodies) containing pigmented nerve cells, that spreads throughout the white substance of the midbrain and receives fibres from the BASAL GANGLIA. DOPAMINE is produced in the substantia nigra, and loss of the pigment cells is a constant finding in PARKINSON'S DISEASE.

Substantia nigra

One of the movement control centers of the brain.
Mentioned in: Parkinson Disease

Soemmerring,

Samuel Thomas von, German anatomist, 1755-1830.
ring of Soemmerring - a mass of lenticular fibers enclosed between the anterior and posterior portion of the lenticular capsule, leaving the pupillary area relatively free.
Soemmerring ganglion - a large cell mass extending forward over the dorsal surface of the crus cerebri from the rostral border of the pons into the subthalamic region. Synonym(s): substantia nigra
Soemmerring ligament - small fibers attaching the lacrimal gland to the periorbita.
Soemmerring muscle - a fasciculus occasionally passing from the thyrohyoid muscle to the isthmus of the thyroid gland. Synonym(s): levator muscle of thyroid gland
Soemmerring spot - an oval area of the sensory retina at the center of which is the central fovea, which contains only retinal cones. Synonym(s): macula retinae

substantia nigra

part of extrapyramidal system (basal ganglia) governing normal motor control (see parkinsonism)

substantia nigra (sb·stanˑ·shē· nīˑ·gr),

n the portion of the mesencephalon (midbrain) whose degeneration is implicated in Parkinson's disease.
Enlarge picture
Substantia nigra.

substantia

pl. substantiae [L.] substance.

substantia alba
the white matter of the spinal cord and the brain.
substantia compacta
compact bone.
substantia gelatinosa
the substance sheathing the posterior horn of the spinal cord and lining its central canal.
substantia grisea
the gray matter of the spinal cord and brain.
substantia grisea centralis
the central gray matter that surrounds the cerebral aqueduct.
substantia nigra
the layer of gray substance separating the tegmentum of the midbrain from the crus cerebri.
substantia propria corneae
layer of transparent lamellated fibrous connective tissue which constitutes the bulk of the cornea; composed of collagen fibers disposed in platelike formations, fibroblasts and ground substance with many nerve fibers but no blood vessels.
substantia propria choroid
loose connective tissue of the choroid.
References in periodicals archive ?
Schierle GS, Hansson O, Leist M, Nicotera P, Widner H, Brundin P: Caspase inhibition reduces apoptosis and increases survival of nigral transplants.
Selective nigral toxicity after systemic administration of 1-methyl-4-phenyl-1,2,5,6-tetrahydropyrine (MPTP) in the squirrel monkey.
Reproducible nigral cell loss after systemic proteasomal inhibitor administration to rats.
Over the years, they have grafted nigral cells from aborted fetuses into the brains of about 250 Parkinson's patients, and despite years of bitter controversy, they've achieved some remarkable successes.
Developmental exposure to PQ or MB alone produced minimal changes, whereas a significant decrease in nigral cell counts was observed after adult exposure.
Examination of the brains of these animals showed not only nigral cell loss with a corresponding striatal dopamine depletion but also neurodegeneration in the locus coeruleus, dorsal motor nucleus of the vagus, and the nucleus basalis of Meynert, a pattern of cell loss that is strikingly similar to that seen in Parkinson's disease and is not observed in any other of the toxicant-induced animal models of Parkinson's disease.
Oxidative stress regulated genes in nigral dopaminergic neuronal cells: correlation with the known pathology in Parkinson's disease.
Acetyl-L-carnitine and alpha-lipoic acid affect rotenone-induced damage in nigral dopaminergic neurons of rat brain, implication for Parkinson's disease therapy.
L-dihydroxyphenylalanine (L-DOPA)-responsive hypokinesia and loss of striatal tyrosine hydroxylase terminals were present by 18 months of age, and loss of nigral dopamine neurons worsened between 18 and 24 months (Caudle et al.
Environmental risk factors and Parkinson's disease: Selective degeneration of nigral dopaminergic neurons caused by the herbicide paraquat.
8 Delivery of AAV2-NRTN into Substantia Nigra (SN) is Safe, Effective, and Supports Nigral Targeting of CERE-120 in Parkinson's Disease (PD) 8
In animal models of nigrostriatal injury, a two weeks treatment with platelet-derived growth factor-BB resulted in long-lasting restoration of striatal dopamine transporter binding sites and expression of nigral tyrosine hydroxylase," said Anders Haegerstrand, Chief Scientific Officer, NeuroNova AB, Stockholm, Sweden.