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.

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 ?
Correlation between substantia nigra and clinical symptoms in Parkinson's disease dementia patients
She argues that the substantia nigra is a natural iron reservoir that simply stores the essential element for use.
Out of 25 cases who are diagnosed to have Parkinson's disease, MRI showed visual decrease in the width of substantia nigra in only 5 cases.
Specifically, the neurons of the striatum extend to the internal globus pallidus (direct pathway), the external globus pallidus (indirect pathway), and the substantia nigra (indirect pathway).
Neuronal vascular relationships in the zona compacta of normal and parkinsonian substantia nigra.
Neurotransmitter receptors and ionic conductances regulating the activity of neurones in substantia nigra pars compacta and ventral tegmental area.
Atrophy of subcortical regions is usually not prominent and the brainstem and cerebellum are often spared; however, loss of pigmented neurons in the substantia nigra may occur.
it is produced as a result of high signal intensity in the tegmentum with preserved normal signal intensity in the red nuclei (eyes of the panda) and lateral portion of the pars reticulata of the substantia nigra (ears of the panda), and hypointensity of the superior colliculi (chin of the panda).
Dopamine released from the substantia nigra, and acting via dopamine D1 receptors, enhances activity through this pathway.
Parkinson's is a devastating neurodegenerative disorder caused by the death of dopamine neurons in a key motor area of the brain, the substantia nigra (SN).
In addition, by treating JNK with a peptide inhibitor derived from a mitochondrial membrane protein, the team was able to induce a two-fold level of protection of neurons in the substantia nigra pars compacta, the brain region devastated by Parkinson's disease.
Dorsal striatum: A pair of nuclear masses that form the basal ganglia, along with the subthalamic nucleus and the substantia nigra.

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