Adrenergic Agonists & Receptors

Question 1

Adrenergic receptors are:

Answer 1

Alpha 1, alpha 2, beta 1, beta 2, beta 3, D1 and D2

Question 2

Directly acting adrenergic agonists are divided into:

Answer 2

Non-selective and selective

Question 3

Directly acting adrenergic agonists which are non selective includes:

Answer 3

Adrenaline
Noradrenaline
Dopamine
Isoproterenol

Question 4

Adrenaline acts on

Answer 4

Alpha 1 & 2, beta 1 & 2

Question 5

When adrenaline is in high dose, which receptor is more sensitive?

Answer 5

Alpha

Question 6

When adrenaline is in low does, which receptor is more sensitive?

Answer 6

Beta

Question 7

When adrenaline is administered, what happens when it binds to a1, b2?

Answer 7

a1: vasoconstriction
b2: increased blood flow to skeletal muscle, bronchodilation

Question 8

Adrenaline is used in

Answer 8

Anaphylactic shock, status asthmaticus

Question 9

NA does not act on

Answer 9

B2

Question 10

NA acts on a1 and b1, which brings about what effects?

Answer 10

a1: vasoconstriction, BP increases (reflex bradycardia)
b1: CO increases, systolic BP increases

Question 11

Dopamine produces dose dependent effects, in low, moderate and high does, what effects are produced respectively?

Answer 11

Low (D1): increase renal blood flow
Moderate (B1): increase cardiac output
High (a1): vasoconstriction

Question 12

Isoproterenol acts on b1 and b2, what effects does it produce?

Answer 12

b1: increase HR, increase CO
b2: TPR and diastolic BP decrease drastically

*b1=heart
b2=blood vessels & bronchioles

Question 13

Directly acting adrenergic drugs which are selective include

Answer 13

phenylephrine (a1) , clonidine (a2) , dobutamine (b1) , salbutamol (b2)

Question 14

Phenylephrine acting on a1 has effects of?

Answer 14

Vasoconstriction: increase BP
Mydriasis(pupil dilation) ONLY

Question 15

Clonidine (a2) causes

Answer 15

Decrease BP: bradycardia
Prevent release of NA

Question 16

Clonidine is used to treat

Answer 16

Hypertension

Question 17

Dobutamine (b1)

Answer 17

Increase HR and CO

Question 18

Salbutamol (B2) causes

Answer 18

Smooth muscle to dilate
Bronchodilation
Vasodilation
Uterine relaxation

Question 19

Salbutamol/ albuterol (b2) treats

Answer 19

Bronchial asthma
Preterm labour

Question 20

State which are inhibitory which are stimulatory adrenergic receptors, and their common effects

Answer 20

a1 + : blood vessels (vasoconstriction), pupil (dilation)
a2 - : inhibit neuro transmission, insulin
b1 + : heart, renin
b2 - : blood vessel (vasodilation), bronchiole (dilation)
b3 -

Question 21

Indirectly acting adrenergic agonists are divided into

Answer 21

releasing agent
uptake inhibitor
MAO/COMT inhibitor

Question 22

Under indirectly acting adrenergic agonists, releasing agent includes

Answer 22

Amphetamine: stimulate release of catecholamines
Effects on:
CNS=delirium
CVS= increase BP

Question 23

Uptake inhibitors include

Answer 23

Amitriptyline:improve mood, tachycardia, blocks reuptake of NA
Cocaine

Question 24

MAO/COMT inhibitors:

Answer 24

MAO present intracellularly and metabolise catecholoamines,COMT present extracellularly and metabolise catecholamines.

Example: selegiline
It inhibits degradation of Dopamine by inhibiting MAO-B (PARKINSON DISEASE)

MAO-A inhibitors: increase synaptic NA con. by inhibiting degradation (DEPRESSION)

Question 25

Mixed acting adrenergic agonist is

Answer 25

ephedrine ( a1 a2 b1 b2)

non selective
Increase NA release
Increase TPR, CO HR
bronchodilation
CNS stimulation

Question 26

B2

Answer 26

Bronchodilation