Neuronal Signaling Flashcards
What two types of receptors can respond to Acetylcholine?
Nicotinic and Muscannic
what type of receptor is a nicotinic receptor?
Ion channel (ach binding allows Na to come in due to conf change)
What type of receptor is a muscannic receptor?
GPCR
Where would you find nicotinic receptors?
In skeletal muscle cells, post synaptic cell neuromuscular junction)
How is an ion channel different to an Ion pump?
Ion channel does not require ATP
How is a neurotransmitter released from the presynaptic cell?
Exocytosis
How many subunits does a nicotinic receptor have?
Five (pentameric)
What structure helps gate the pore in a nicotinic receptor?
m2 alpha helices
How are ions attracted through the pore in a nicotinic receptor after Ach binds?
Na+ ions are attracted into the pore through aspartic acid and glutamic acid residues
What does the rapid influx of Na ions through the nicotinic receptor on post synaptic cell cause to happen?
Depolarisation of the membrane
How do voltage gated ion channels work?
Membrane depolarisation causes positively charged voltage sensing helices to move to the extracellular side of the membrane (d-). This causes pore to open.
How are voltage gated ion channels turned off?
They have an inactivating segment.
