Section 2d Cholinergics genergal Flashcards
What receptor is always on the post synaptic neuron?
Nicotinic receptor
What is recycled back into the presynaptic neuron in cholinergic transmission
choline… not ACh
What enzyme transfers the acetyl group from acetyl-CoA to Choline to make ACh?
Choline acetyltransferase (ChAT
What are the 3 sources of choline?
- Choline recycled from the synaptic cleft
- plasma based stores - transported to brain as phosphatidylcholine
- stored in phospholipid as phosphorylcholine
Where does Acetyl CoA come from?
- mainly from glycolysis - produced by pyruvate dehydrogenase
- synthesis occurs at inner membrane of mito and is transported out via citrate
What is the rate limiting step of ACh synthesis?
choline uptake
What does hemicholinium do?
inhibits transport of choline back into pre-synaptic cell
What does vesamicol do?
inhibits H+/ACh antiporter to get ACh into vesicles
What does Botulinum toxin do?
prevents exocytosis of presynaptic vesicle –> blocking ACh release
What does black widow spider venom do?
causes all ACh to releaes into the synapse
Where are M1’s found?
gastric parietal cells
Where are M2 found?
cardiac cells, and smooth muscle cells
Where are M3 found?
bladder, exocrine glands, and smooth muscle cells
Which M receptors facilitate excitation of the cell? And how do they work?
M1, M3, and M5
Gq stimulates PLC –> Ca2+ release
Which M receptors suppress cellular excitability? And how do they work?
M2 and M4
inhibit AC and activate K+ channels
