Easy Flowchart Of Neuromuscular Transmission-Physiology

A neuromuscular junction (or myoneural junction) is a chemical synapse between a motor neuron and a muscle fiber.[1] It allows the motor neuron to transmit a signal to the muscle fiber, causing muscle contraction.
Muscles require innervation to function-and even just to maintain muscle tone, avoiding atrophy. In the neuromuscular system nerves from the central nervous system and the peripheral nervous system are linked and work together with muscles.[2] Synaptic transmission at the neuromuscular junction begins when an action potential reaches the presynaptic terminal of a motor neuron, which activates voltage-gated calcium channels to allow calcium ions to enter the neuron. Calcium ions bind to sensor proteins (synaptotagmin) on synaptic vesicles, triggering vesicle fusion with the cell membrane and subsequent neurotransmitter release from the motor neuron into the synaptic cleft. In vertebrates, motor neurons release acetylcholine (ACh), a small molecule neurotransmitter, which diffuses across the synaptic cleft and binds to nicotinic acetylcholine receptors (nAChRs) on the cell membrane of the muscle fiber, also known as the sarcolemma. nAChRs are ionotropic receptors, meaning they serve as ligand-gated ion channels. The binding of ACh to the receptor can depolarize the muscle fiber, causing a cascade that eventually results in muscle contraction.
Neuromuscular junction diseases can be of genetic and autoimmune origin. Genetic disorders, such as Duchenne muscular dystrophy, can arise from mutated structural proteins that comprise the neuromuscular junction, whereas autoimmune diseases, such as myasthenia gravis, occur when antibodies are produced against nicotinic acetylcholine receptors on the sarcolemma.Acetylcholine receptors
Ion channel linked receptor
Ions
Ligand (such as acetylcholine)
When ligands bind to the receptor, the ion channel portion of the receptor opens, allowing ions to pass across the cell membrane.
Acetylcholine is a neurotransmitter synthesized from dietary choline and acetyl-CoA (ACoA), and is involved in the stimulation of muscle tissue in vertebrates as well as in some invertebrate animals. In vertebrate animals, the acetylcholine receptor subtype that is found at the neuromuscular junction of skeletal muscles is the nicotinic acetylcholine receptor (nAChR), which is a ligand-gated ion channel. Each subunit of this receptor has a characteristic "cys-loop", which is composed of a cysteine residue followed by 13 amino acid residues and another cysteine residue. The two cysteine residues form a disulfide linkage which results in the "cys-loop" receptor that is capable of binding acetylcholine and other ligands. These cys-loop receptors are found only in eukaryotes, but prokaryotes possess ACh receptors with similar properties.[4] Not all species use a cholinergic neuromuscular junction; e.g. crayfish and fruit flies have a glutamatergic neuromuscular junction.[3]
AChRs at the skeletal neuromuscular junction form heteropentamers composed of two α, one β, one ɛ, and one δ subunits.[9] When a single ACh ligand binds to one of the α subunits of the ACh receptor it induces a conformational change at the interface with the second AChR α subunit. This conformational change results in the increased affinity of the second α subunit for a second ACh ligand. AChRs therefore exhibit a sigmoidal dissociation curve due to this cooperative binding.[4] The presence of the inactive, intermediate receptor structure with a single-bound ligand keeps ACh in the synapse that might otherwise be lost by cholinesterase hydrolysis or diffusion. The persistence of these ACh ligands in the synapse can cause a prolonged post-synaptic response.[10]

[@Simplensweett]

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[@tamanna1852]

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[@danxoxxo]

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[@neelisettihemanth8294]

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[@Dr.KareemaTabassum]

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[@priyanaik3425]

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[@nikhilsaikarri5900]

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[@aadhilshaik7022]

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[@sandeepkaur4848]

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[@shansss_]

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[@Dr.KareemaTabassum]

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[@nadaelbery7894]

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[@Dr.KareemaTabassum]

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[@ananyasimha1948]

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[@mahimamanohar1018]

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[@Dr.KareemaTabassum]

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[@sumaiyaislam8986]

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[@thesimple7956]

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[@muhammadhuzaifa8649]

the rest of the video is good but end plate potential will become zero with the entry of sodium only then action potential in the adjacent part will generate .
thanks me later .

[@themedguy8100]

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[@HassanAli-nx4nh]

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[@Korisahab144]

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[@MonishaVKmch]

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[@thesimple7956]

Extracellular fluid: simply remember as the fluid present outside the cell

[@muhammadhuzaifa8649]

the rest of the video is good but end plate potential will become zero with the entry of sodium only then action potential in the adjacent part will generate .
thanks me later .

[@muhammadhuzaifa8649]

the rest of the video is good but end plate potential will become zero with the entry of sodium only then action potential in the adjacent part will generate .
thanks me later .