Neuromuscular Junctions

• What is a neuromuscular junction?


  A synapse between a motor neurone and a muscle cell
• What do neuromuscular junctions use?


  The neurotransmitter Ach, which binds to cholinergic receptors called NICOTINIC cholinergic receptors
• How do neuromuscular junctions work?


  pretty much the same way as cholinergic synapses - but a few differences
• briefly list the 3 Ways in which neuromuscular junctions are different to cholinergic synapses in how they work?


  the postsynaptic membrane has lots of folds that form CLEFTS

  • These clefts store the enzyme that breaks down Ach
  • this enzyme is acetylcholinesterase - AChE
• list one of the ways in which neuromuscular junctions are different to cholinergic synapses in how they work?


  the postsynaptic membrane has more receptors than other synapses
• list one of the ways in which neuromuscular junctions are different to cholinergic synapses in how they work?


  Ach is AWAYS EXCITATORY at a neuromuscular junction.

  • So when a motor neurone fires an AP, it normally triggers a RESPONSE in a muscle cell
  • this is not always the case for a synapse between 2 neurones