ANS intro Flashcards
Exam 4
1
Q
Two main neurotransmitters
A
- ACh
- NE
2
Q
Cholinergic
A
-fibers that secrete ACh
3
Q
Adrenergic
A
-fibers that secrete NE
4
Q
Synthesis of ACh
A
- choline comes in with Na+
- choline binds to Acetyl-CoA and gets made into ACh
- calcium comes into cell and causes release of ACh into synaptic cleft
5
Q
Preganglionic nerve fibers
A
In ANS release ACh
6
Q
Postganglionic nerve fibers
A
- only certain release ACh
- those that activate PNS
- those that go to the somatic nervous system
- those that activate sweat glands (only somatic nervous system response activated by ACh)
7
Q
Norepinephrine
A
released by postganglionic nerve fibers
8
Q
Epinephrine
A
- released by adrenal medulla
- preganglionic sympathetic neurons that release ACh
- ACh acts on nicotinic receptors of adrenal gland
9
Q
Dopamine
A
- released by postganglionic sympathetic neurons
- effect renal vascular smooth muscle
10
Q
Adrenergic fibers
A
-only found in somatic nervous system
11
Q
Synthesis of NE
A
- tyrosine goes through hydroxylation into dopa
- dopa goes through decarboxylation into dopamine
- dopamine is transported in a vesicle where the rest of synthesis takes place
- dopamine goes through hydroxylation into norepinephrine
- in the adrenal medulla NE goes through methylation into epi
12
Q
Acetylcholine receptors
A
- Muscarinic
- Nicotinic
13
Q
Muscarinic subtypes and location
A
- M1: nerves
- M2: heart, nerve, smooth muscle
- M3: exocrine glands, smooth muscle, endothelium
- M4: CNS
- M5: CNS, vascular endothelium
14
Q
Nicotinic subtypes and location
A
- N(n) or N1: CNS, postganglionic cell body
- N(m) or N2: skeletal muscle neuromuscular junctions
15
Q
Cholinergic receptors
A
- ACh binds equally to N & M receptors, but drugs do not
- drug that blocked primarily nicotinic receptors would affect everything
- drug that blocked muscarinic receptors would block the PNS response and sweating
