7: Autonomic Pharmacology II

Question 1

What binds to nicotinic receptors?

Answer 1

Acetylcholine (ACh)

Question 2

Where are nicotinic receptors found?

Answer 2

Autonomic ganglia (both sympathetic and parasympathetic)

Skeletal muscle

Question 3

Nicotinic ACh receptors are made up of five different ___.

Answer 3

subunits

Question 4

The entry of which ion triggers neurotransmitter release from pre- and post-sympathetic ganglia?

Answer 4

Ca²⁺

Question 5

What are the two types of ACh receptor?

Answer 5

Nicotinic (symp + parasymp among many other places)

Muscarinic (parasymp only + many other places)

Question 6

Which types of cholinergic receptor may cause a cellular response?

Answer 6

Nicotinic

Muscarinic

i.e the only two types of ACh receptor

Question 7

Which type of ACh receptor causes a cellular response at parasympathetic junctions?

Answer 7

Muscarinic

parasympathetic nervous system only

Question 8

What does M₁ receptor activation cause?

Answer 8

Increased gastric acid secretion

Question 9

What does M₂ receptor activation cause?

Answer 9

Decreased heart rate

Question 10

What does M₃ receptor activation cause?

Answer 10

Bronchoconstriction

bronchial smooth muscle constriction

Question 11

What does ß₁ activation cause?

Answer 11

Increased HR and force of contraction

Question 12

What does ß₂ activation cause?

Answer 12

Bronchodilation

Vasodilation

Question 13

What does α₁ activation cause?

Answer 13

Vasoconstriction

Question 14

What does α₂ activation cause?

What kind of physiological control mechanism is this?

Answer 14

Inhibition of NA release

Negative feedback

Question 15

α₂ receptors are sometimes found before the synapse - what implication does this have?

Answer 15

α₂ receptors inhibit NA release

Reduce the amount of NA released by negative feedback (excessive NA release triggers more α₂ receptors)

Question 16

Cocaine (stimulates / inhibits) NA release resulting in (increased / decreased) adrenoceptor stimulation.

Answer 16

stimulates , increased

Question 17

Cocaine’s tendency to increase NA release causes vasoconstriction and cardiac arrythmia.

Why?

Answer 17

NA activates:

α₁ adrenoceptors ► vasoconstriction

ß₁ adrenoceptors ► increased HR and force of contraction

Question 18

Which drug, commonly used in treatment of ADHD, has similar effects on NA release and adrenoceptor activation as cocaine?

Answer 18

Amphetamine

Question 19

Which class of drugs block the adrenoceptors responsible for vasoconstriction, and what are these adrenoceptors?

Answer 19

Alpha blockers (e.g prazosin)

α₁ adrenoceptors

Question 20

Which class of drug blocks cardio-selective adrenoceptors to treat angina and hypertension?

Which adrenoceptor does this refer to?

Answer 20

Beta blockers (e.g atenolol)

B₁ adrenoceptors

Question 21

Which inhaled medication binds to adrenoceptors to cause bronchodilation in asthma?

Which adrenoceptor is this?

Answer 21

SABAs/LABAs (e.g salbutamol / salmeterol)

ß₂ adrenoceptors

Question 22

Which drug non-selectively blocks all muscarinic receptors and is used to treat bradycardia?

Answer 22

Atropine