6: ANS Receptors

Question 1

ANS Synapse #1: Pre-ganglionic to Postganglionic: neurotransmitter and receptor type

Answer 1

Neuro: Ach
Receptor: nicotinic cholinergic

Question 2

Why are nicotinic cholinergic receptors named as such?

Answer 2

Nicotine also binds these (the exogenous ligand, whereas Ach is the endogenous ligand)

Question 3

What happens when Ach binds to a nicotinic receptor?

Answer 3

Na enters cell -> depolarization + increased excitability

Question 4

Parasymp Postganglionic -> target tissue: neurotransmitter and receptor

Answer 4

Neuro: Ach
receptor: muscarinic cholinergic receptor

Question 5

Sympathetic Postganglionic -> target tissue: neurotransmitter and receptor

Answer 5

Neuro: norepinephrine
Receptor: adrenergic receptors

Question 6

M1, M3, M5 G protein activation

Answer 6

Gq proteins - increased IP3 -> increased Ca

Question 7

M2, M4 G protein activation

Answer 7

Gi/o proteins -> decreased adenylyl cyclase activity

Question 8

A1 G protein activation

Answer 8

Gq proteins -> IP3 -> intracellular Ca

Question 9

A2 G protein activation

Answer 9

Gi protein -> decreased in cAMP

Question 10

B1, B2, B3: G protein activation

Answer 10

Gs protein -> increase in cAMP

Question 11

M1R: functions outside of ANS

Answer 11

Some have nothing to do with ANS, have memory functions, etc.

Question 12

M5

Answer 12

In CNS, not involved with ANS

Question 13

M2 major function and how it works

Answer 13

Cardiac conduction system: K efflux out of cells -> hyperpolarizes -> decreases HR and conduction

Question 14

M4 function

Answer 14

We dont know

Question 15

What symp receptor is found on platelets, and what’s its function

Answer 15

A2, increases clotting activity

Question 16

Major parasymp receptor in the heart

Answer 16

Beta1

Question 17

Where is B3 found?

Answer 17

White and brown adipose

Question 18

Preganglionic fibers that synapse in adrenal medulla instead of sympathetic ganglia: neurotransmitter and receptor

Answer 18

Neuro: Ach
Receptor: nicotinic cholinergic receptor

Question 19

What cell type in the adrenal medulla has the nicotinic cholinergic receptors?

Answer 19

Chromaffin cells

Question 20

What do chromaffin cells release?

Answer 20

Epi and other catecholamines (into the blood)

Question 21

Signs of sympathetic activity in an emergency setting

Answer 21

Increased HR, pupil dilation, pallor, diaphoretic, increased respiratory rate (secondary to HR), goosebumps, decreased urine output, increased clotting

Question 22

Signs of dysautonomia

Answer 22

Overactive bowel and urinary excretion, low BP, low HR, pupil constriction, decreased ability to clot