sympathomimetics

Question 1

α adrenoreceptors have greater affinity for synthetic or natural catecholamines

Answer 1

natural

Question 2

α1 higher affinity for phenylephrine or clonidine

Answer 2

phenylephrine(Clonidine selectively binds to α2 rec)

Question 3

α1 is which g linked receptor

Answer 3

Gq

Question 4

α2 is which g linked receptor

Answer 4

Gi

Question 5

what is the location of α1 and α2 receptors?

Answer 5

α1 — post synaptic memberane of effector organs V.C (skin & abdominal viscera
α2 on presynaptic memberane and also on b cells of pancreas

Question 6

functions of α1

Answer 6

vasoconstriction
mydriasis
urinary retention
glycogenolysis
Dec renin release

Question 7

functions of α2

Answer 7

feedback inhibition of N.E release
insulin release reduction

Question 8

β receptor — affinity for natural or synthetic catecholamines

Answer 8

synthetic

Question 9

β1 — affinity for epi and N.E

Answer 9

Equal

Question 10

β2 — affinity for epi and N.E

Answer 10

more for epi

Question 11

action of β1

Answer 11

ACTION ON HEART
HR inc
Contractility inc
AV conduction inc
ACTION ON KIDNEY
Renin Inc
BP inc

Question 12

β2 action

Answer 12

bronchodilation
Skeletal vasculature bed– vasodilation– p.r dec
insulin inc
gi motility dec
inhibition of labor

Question 13

CNS penetration of Catecholamines

Answer 13

poor

Question 14

why are catechlamines rapidly deactivated

Answer 14

rapid metabolization by COMT

Question 15

Non Catecholamines: Amphetamine. Long duration →why?

Answer 15

Aren’t inactivated by COMT.
b) Poor substrates for MAO.
2. High CNS penetration.

Question 16

what is the effect of epi on systolic BP

Answer 16

INCREASES
due to action on alpha 1 and Beta 1 receptors

Question 17

what is the effect of epi on diastolic BP

Answer 17

DEC
dueto action on beta 2 receptor

Question 18

therapeutic use of epi

Answer 18

anaphylaxis
small amount with local anesthetic to inc duration of anesthesia(vasoconstriction)

Question 19

why epinephrine isn’t used in a pt with hyperthyroidism

Answer 19

Due to ↑ adrenergic receptors on vasculature of hyperthyroid individual.

Question 20

interaction with cocaine

Answer 20

cocaine inhibits reuptake of catecholamines by adrenergic neuron→ Exaggerated C.V. action.

Question 21

which receptors does nor epi acts on

Answer 21

alpha 1 , alpha 2
beta 1

Question 22

cvs effect of n.e

Answer 22

α1: V.C→ ↑ Systolic & diastolic B.P→ baroreceptors→ ↑vagal activity→ reflex bradycardia (but with no effect on + ve inotropic effect).

Question 23

which drug blocks the vagal stimulation effect of n.e

Answer 23

atropine

Question 24

therapeutic use of n.e

Answer 24

cardiogenic shock

Question 25

use of isoproternol

Answer 25

atrioventricular block, cardiac arrest

Question 26

action on receptors of isoproterenol

Answer 26

beta 1, beta 2

Question 27

which drug is prefered for cardiogenic shock dopamine or nor epi

Answer 27

dopamine Preferred over N.E→ Why? because N.E ↓ blood flow to kidney→ renal shut down

Question 28

what is the action of dopamine on the receptor that it acts(beta 1, alpha 1, dopaminergic receptors)

Answer 28

Low dose→ β1→:+ve inotropic & chronotropic. *High dose→ α1→ V.C →↑ B.P *D2 & D1→ V.D→ ↑ blood flow to kidney

Question 29

therapeutic use of dobutamine

Answer 29

CHF

Question 30

which drug ↑ C.O with little change on cardiac rate

Answer 30

dobutamine

Question 31

which receptor does dobutamine acts on

Answer 31

beta 1

Question 32

therapeutic use of oxymetazoline

Answer 32

nasal decongestant(locally)

Question 33

side effect of oxymetazoline

Answer 33

rebound congestion

Question 34

which adrenergic agonist is used in treatment of supraventicular tachycardia

Answer 34

methoxamine

Question 35

which adrenergic agonist is used in overcoming hypotension during surgery involving halothane

Answer 35

methocamine

Question 36

which is the only adrenergic drug that doesn't trigger cardiac arrhythmia which is sensitized by these general anesthetics

Answer 36

methoxamine

Question 37

which receptors does methoxamine acts on

Answer 37

α1 ( α1 > α2)

Question 38

therapeutic use of amphetamines

Answer 38

adhd, narcolepsy, appetite control

Question 39

moa of amphetamine

Answer 39

non vesicular release of catecholamines is enhanced by amphetamine

Question 40

drugs in indirect acting adrenergic agonist

Answer 40

amphetamine cocaine tyramine

Question 41

drugs in mixed adrenergic agonist

Answer 41

ephedrine pseudoephedrine