Definition of end plate : a complex terminal treelike branching of the axon of a motor neuron that contacts with a muscle fiber.
What is end plate in biology?
Cell Biology. a specialized area on the surface of a muscle fiber where a motor neuron makes contact with the muscle, consisting of an irregularly shaped trough into which the terminal portion of the axon fits.
What is end plate used for?
As the intermediary layer between the bones and discs, the endplates provide strength and stability to help prevent vertebral fracture and to protect the delicate discs. Because of their porousness, they also serve as the medium through which blood and nutrients flow from capillaries in the bone to cells in the discs.
What is a vertebral end plate?
A vertebral end plate is the transition region where a vertebral body and intervertebral disc interface with each other. A vertebral end plate is commonly described as consisting of 2 layers: Cartilaginous layer (also called cartilaginous endplate) that fuses with the disc.
Where is the end plate?
end-plate potential (EPP), chemically induced change in electric potential of the motor end plate, the portion of the muscle-cell membrane that lies opposite the terminal of a nerve fibre at the neuromuscular junction.
What is Myofibrillar?
Myofibrils are bundles of protein filaments that contain the contractile elements of the cardiomyocyte, that is, the machinery or motor that drives contraction and relaxation.
What causes Epps?
EPP are caused mostly by the binding of acetylcholine to receptors in the postsynaptic membrane. There are two different kinds of acetylcholine receptors: nicotinic and muscarinic.
Does endplate cause pain?
In fact, low back pain caused by endplate injuries is quite common in clinical research. Epidemiological investigations indicate that in the population without low back pain, the incidence rate of endplate injuries is about 30% [30].
What is endplate made of?
The vertebral endplates are composed of both bone and cartilage tissue.
What are end plate changes?
Background. Vertebral endplate (Modic) changes are bone marrow and endplate lesions visible in magnetic resonance imaging (MRI). They are shown to be associated with degenerative intervertebral disc disease [1–3].
Does end plate potential propagate?
The end-plate potential is a graded potential (it is not all-or-none) that propagates electrotonically to the neighboring patch of muscle fiber membrane where it initiates an action potential on the muscle much like it does on unmyelinated nerves.
What is motor end plate?
The specialized postsynaptic region of a muscle cell. The motor endplate is immediately across the synaptic cleft from the presynaptic axon terminal. Among its anatomical specializations are junctional folds which harbor a high density of cholinergic receptors. Year introduced: 1991(1975)
Is motor end plate the same as neuromuscular junction?
Neuromuscular junctions, also called motor end plates, are specialised chemical synapses formed at the sites where the terminal branches of the axon of a motor neuron contact a target muscle cell.
What is difference between motor unit and motor end plate?
Motor Units. Each muscle fiber receives only one motor end plate, but the number of muscle fibers innervated by a single alpha motor neuron axon varies from a few to many. The aggregate of a motor neuron axon and all the muscle fibers it innervates is called a motor unit (Fig. 24.3).
Why is synapse called a motor end plate?
The terminal region of the axon gives rise to very fine processes that run along skeletal muscle cells. Along these processes are specialized structures known as synapses. The particular synapse made between a spinal motor neuron and skeletal muscle cell is called the motor endplate because of its specific structure.
What is a motor end plate quizlet?
– Motor end plate—the muscle fiber membrane in which the sarcolemma is tightly folded and where nuclei and mitochondria are abundant. – Synaptic cleft—space between the synaptic end bulb and motor end plate.
What receptors do motor end plates have?
The acetylcholine receptors on the motor end plate are concentrated along the shoulders of the folds defining secondary clefts in the sarcolemma. The receptors are made up of five subunit proteins forming a cylinder with a central pore ion channel. Each receptor unit has two sites for acetylcholine binding.
What is the motor end unit?
The motor end plate is where neurotransmitter is released from the neuron to excite the muscle fiber. There is one motor endplate per muscle fiber. Recall that a motor unit is defined as a group of muscle fibers innervated by a single neuron.
When reaches the end of the axon?
When the 5 reaches the ends of the axon, the neurotransmitter is released and diffuses to the muscle cell membrane to combine with receptors there. The combining of the neurotransmitter with the muscle membrane receptors causes a change in permeability of the membrane, resulting in 6 of the membrane.
