Neuromuscular junction disease

Overview
Neuromuscular junction disease is a medical condition where the normal conduction through the neuromuscular junction fails to function correctly.

Autoimmune
In diseases such as myasthenia gravis, the EPP fails to effectively activate the muscle fiber due to an autoimmune reaction against acetylcholine receptors, resulting in muscle weakness and fatigue.

Myasthenia gravis is caused most commonly by auto-antibodies against the acetylcholine receptor.

It has recently been realized that a second category of gravis is due to auto-antibodies against MuSK.

A different condition, Lambert-Eaton myasthenic syndrome, is usually associated with presynaptic antibodies to the voltage-dependent calcium channel.

It is possible for these conditions to coexist.

Toxins
Various toxins, such as botulinum toxin prevent the release of acetylcholine, resulting in muscle paralysis.