Neuromuscular junction


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junction

 [jungk´shun]
a place of meeting or coming together. adj., adj junc´tional.
atrioventricular junction in the conduction system of the heart, the junction between the atrioventricular node and the nonbranching portion of the bundle of His.
cementoenamel junction the line at which the cementum covering the root of a tooth meets the enamel covering the crown.
gap junction a narrowed portion of the intercellular space, containing channels linking adjacent cells and through which can pass ions, most sugars, amino acids, nucleotides, vitamins, hormones, and cyclic AMP. In electrically excitable tissues the gap junctions serve to transmit electrical impulses via ionic currents and are known as electrotonic synapses; they are present in such tissues as myocardial tissue.
myoneural junction (neuromuscular junction) the site of junction of a motor nerve fiber and a skeletal muscle fiber that it innervates. The discoid expansion of the terminal branch of the axon forms the motor end plate, the neurotransmitter that diffuses across the synapse is acetylcholine.
sclerocorneal junction limbus (def. 2).
ureteropelvic junction the area where the renal pelvis meets the ureter.

my·o·neu·ral junc·tion

the synaptic connection of the axon of the motor neuron with a muscle fiber. See: motor endplate.

junction

(junk'shun) [L. junctio, a joining]
The place of union or coming together of two parts or tissue layers.

amelodentinal junction

Dentinoenamel junction.

atrioventricular junction

The area of cardiac conduction pathway connecting the AV node with the atrioventricular bundle.

cementodentinal junction

The interface of dentin and cementum of the tooth. Synonym: dentinocemental junction

cementoenamel junction

The line around the tooth that marks the boundary between the crown and root of the tooth; the interface between enamel and cementum.

costochondral junction

The articulation or meeting place of the bony rib and its costal cartilage.

cervicomedullary junction

The nexus between the most superior part of the spinal cord and the medulla oblongata of the brainstem.

dentinocemental junction

Cementodentinal junction.

dentinoenamel junction

The plane or interface between the dentin of the tooth and the enamel crown; histological sections show it to be a scalloped boundary at the site of the basement membrane which separated the cell layers that formed the calcified enamel and dentin. Synonym: amelodentinal junction

dentogingival junction

The interface and zone of attachment between the gingiva and enamel or cementum of the tooth. It holds in place the junctional or attachment epithelium.

interneuronal junction

Synapse.

liquid junction

The point in a potentiometric reference electrode measurement system at which the reference solution makes contact with the test solution. An example is pH reference electrode.

mucocutaneous junction

The junction between the skin and a mucous membrane.

mucogingival junction

A scalloped, indistinct boundary between the gingiva and the oral mucosa on the alveolar process. The coral color of gingiva may be contrasted with the more vascular oral mucosa. Also called the mucogingival line.
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MYONEURAL JUNCTION

myoneural junction

The axon terminal of a motor neuron, synaptic cleft, and sarcolemma of a muscle cell. Synonym: neuromuscular junction
See: illustration

neuromuscular junction

Myoneural junction.

saphenofemoral junction

The merging of the saphenous and femoral veins in the inguinal region.

sclerocorneal junction

The meeting point between the sclera and the cornea marked on the external surface of the eyeball by the outer scleral sulcus.
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SQUAMOCOLUMNAR JUNCTION: Squamocolumnar junction of the distal esophagus (seen endoscopically)

squamocolumnar junction

1. The point in the cervical canal at which the squamous and columnar epithelia meet. As most cervical cancers begin in this area, it is important to obtain cells from this location for the Pap test.
2. The point above the lower esophageal sphincter where the squamous epithelium of the esophagus and the columnar epithelium of the stomach meet.
Synonym: transition zone. See: illustration

tight junction

A part of the junctional complex at the lateral interface between epithelial cells; also called zonula occludens.

neuromuscular junction

the area of contact between a MOTOR NEURON and a MUSCLE FIBRE.

Neuromuscular junction

The site at which nerve impulses are transmitted to muscles.
References in periodicals archive ?
Caption: Figure 4: The quantity of neuromuscular junctions based on esterase staining.
Caption: Figure 1: Muscle 4 neuromuscular junction. Bruchpilot and corresponding active zone distribution in synaptic boutons from transgenic Drosophila melanogaster larvae.
To recreate more realistic in vitro neuromuscular junctions, Uzel and his colleagues fabricated a microfluidic device with two important features: a three-dimensional environment, and compartments that separate muscles from nerves to mimic their natural separation in the human body.
Aside from impairing movement in aging animals, a new functional set point in neuromuscular junctions could put the synapse at risk for developing neurodegeneration - the hallmark of disorders such as Alzheimer's and Parkinson's diseases, Mahoney said.
At the neuromuscular junction, where [Ca.sub.V]2.1 channels are the exclusive mediators of acetylcholine release, no compensatory [Ca.sup.2+] channel expression was found [23].
1 describes the combined auto-immune response resulting in destruction of neuromuscular junction in the Lambert-Eaton myaesthenic syndrome.
These toxins block the release of the neurotransmitter acetylcholine at the neuromuscular junction, preventing muscle contraction and resulting in a characteristic floppy paralysis.
Our targets in this endeavor, nicotinic acetylcholine receptors and related ligand-gated ion channels, are widely distributed throughout the periphery, autonomic ganglia, and neuromuscular junction. This class of receptors is implicated in numerous physiological processes and pathologies including Alzheimer's disease, Parkinson's disease, Myasthenia gravis, some forms of epilepsy, schizophrenia, cognition, locomotion, inflammation, pain, reward, and addiction.
By acting specifically on motor nerve terminals at the neuromuscular junction, it inhibits the release of acetylcholine from the cholinergic nerve endings and exhibits muscle relaxant effects.
The neuromuscular junction is the place where the nerve and muscle are in close proximity and where the acetylcholine-containing vesicles are located in the nerve terminal.
It is an uncommon autoimmune syndrome caused by failure of the neuromuscular junction as a result of formation of antibodies against acetylcholine nicotinic postsynaptic receptors.

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