Acetylcholine Flashcards

1
Q

When is ACh released from the post ganglion in the sympathetic nervous system?

A

In sweat glands.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the receptor for ACh at the preganglionic synapse, and post ganglionic synapse respectively?

A

Pre- nicotinic

Post- muscarinic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Where does ACh act when released parasympathetically and what effects does it have? (4)

A
  • heart- M2 receptors- negative chronotropy
  • bronchi- M3 receptors- bronchoconstriction
  • bladder- M3 receptors- bladder contraction
  • glands- M3 receptors- increased secretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How is acetylcholine synthesised?

A

From acetyl coA and choline using choline acetyl transferase enzyme, in the pre synaptic knob.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What packages ACh into vesicles ready for release?

A

Vesicular ACh transporter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How is ACh released from the pre synaptic knob when an AP arrives?

A

Arrival of an AP causes voltage gated calcium channels to open and calcium ions to influx into the knob.
Calcium binds to synaptotagmin to form a snare complex.
The vesicle if brought to the membrane edge and ACh is released through the pore in the snare complex.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How is ACh action terminated? What is it converted to? What happens to the components?

A

Using acetylcholine esterase into acetate and choline.
The acetate diffuses into the surrounding medium, where as the choline is recaptured into the pre-synaptic knob by high affinity choline uptake system and is used for further ACh production.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the affect of parasympathetic innervation on the eye?

A

-ciliary muscles and sphincter muscles both contract.
Allows focus on nearby objects.
Decreased intra ocular pressure as trabecular meshwork is opened.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is glaucoma?

A

An abnormally raised intra ocular pressure which can cause damage to the optic nerve, and eventually blindness.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the causes of glaucoma? (5)

A
Steroids 
Diabetes 
Ethnicity 
Sex 
Age
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which branch of the ANS is ACh always released from?

A

Parasympathetic branch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly