NEUROMUSCULAR JUNCTION

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The neuromuscular junction (NMJ) is a synaptic connection between the terminal end of a motor nerve and a muscle (skeletal/ smooth/ cardiac). It is the site for the transmission of action potential from nerve to the muscle. It is also a site for many diseases and a site of action for many pharmacological drugs.

It is a junction, connection between a neuron and a muscle fibre.
The structure of neuromuscular Junction can be divided into 3 categories
➡️ Presynaptic part( terminal end of an Axon). It consists of vesicles which contains Acetylcholine. 

➡️ Synaptic cleft (space between the neuron and the muscle fibre.

➡️ Postsynaptic part( site of action or the muscles fibre. It contains receptors for neurotransmitters eg. Acetylcholine)

PHYSIOLOGY 
The nerve impulses reaches the terminal end of a axon, the following will take place.

➡️ The will be opening of the ca+(voltage ⚡) gated channel.

➡️ This will cause the release of the vesicles.

➡️ Vesicles will rupture and release Acetylcholine.

➡️ Acetylcholine will cross through the synaptic cleft and bind with the Acetylcholine Receptors in the motor end plate of the muscle fibre.

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