substantia nigra


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Related to substantia nigra: dopamine, Cranial nerves, basal ganglia, striatum

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.

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
References in periodicals archive ?
Dopamine is produced in the neurons of the pars compacta region of the substantia nigra within the basal ganglia, but also in other areas of the CNS and throughout the body (Herrero et al., 2002).
GABAergic projection from the ventral tegmental area and substantia nigra to the periaqueductal gray region and the dorsal raphe nucleus.
Penetration of Light in the Rat Substantia Nigra. As mentioned in Section 2, the cannula was implanted in the substantia nigra with a transcerebellar trajectory inclined 20[degrees] on the sagittal plane in order for the optical probe to detect light coming from the front, top, and lateral of the animal head.
Four equally spaced sections from each subject containing the substantia nigra were used for analysis.
In this paper we have tested pole-climbing time in Parkinson's disease mice, determined the levels of DA and HVA in striatum, analyzed the levels of dopamine receptor 1 and dopamine receptor 2 in striatum and the level of Caspase-3 protein in substantia nigra, by which we can investigate the mechanism of extract of Acanthopanax senticosus Harms against Parkinson's disease.
"Eventually, this reaches the substantia nigra and the higher cerebellar neurons.
The cerebral cortex in MSA is usually significantly smaller than in normal control patients, the degree of atrophy reflecting the duration of disease rather than the age of the patient.11 In addition, there may be a specific and progressive cerebral atrophy affecting the frontal lobes12 and the motor/premotor areas.13 The substantia nigra and locus caeruleus in the midbrain and pons respectively are pale due to loss of pigment.
Although it is possible that both of the diseases may lie on a continuum of a single disease that begins with ADHD manifested in childhood and continues into adulthood as dementia with Lewy bodies "when neuronal loss and gliosis in the substantia nigra, locus coeruleus, and nucleus basalis of Meynert occur," the authors doubted that this hypothesis could be accurate because low dopamine levels in ADHD are not initially associated with Parkinsonlike or DLB symptoms.
The loss of dopaminergic neurons in the substantia nigra region of the brain is 1 pathological hallmark in patients with PD.
Some studies have detected axon degeneration in the substantia nigra, a part of the brain that controls movement, following MDMA use (Ricaurte, Yuan & McCann 2000; McKenna & Peroutka 1990).

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