General

Question 1

3 mechanisms of action

Answer 1

Direct-acting

Indirect-acting

Mixed-acting
(Direct activation + indirect release)

Question 2

Direct-acting drugs

Answer 2

stimulate postsynaptic receptors

Selective vs. Nonselective

NOT reduced by pretreatment w/ Reserpine

Question 3

Indirect-acting drugs

Answer 3

increase availability of NE or E

• -releasing or displacing NE from sympathetic nerve varicosities
• -Blocking transport of NE into neurons (i.e. cocaine)
• -Blocking metabolizing enzymes (i.e. MAO or COMT)

ABOLISHED by pretreatment w/ Reserpine

Releasing agents vs. Cocaine, MAO, COMTI, etc.

Question 4

Mixed-acting drugs

Answer 4

direct activation + indirect release

REDUCED by pretreatment w/ Reserpine

Question 5

Selective Direct-acting adrenergic agonists

Answer 5

a1- phenylephrine
a2- clonidine
b1- dobutamine
b2- terbutaline

Question 6

Non-selective Direct-acting adrenergic agonists

Answer 6

a–oxymetazoline
b–isoproterenol
a and b–epinephrine
a and b1–norepinephrine

Question 7

Indirect-acting releasing agents

Answer 7

Tyramine

Amphetamines

Question 8

Pretreatment w/ Reserpine…

Direct-acting drug

Answer 8

No effect,

may even increase b/c upregulation of receptors/enhancement of signalling pathway due to chronic treatment of reserpine

Question 9

Pretreatment w/ Reserpine…

Indirect-acting

Answer 9

Abolished

Question 10

Pretreatment w/ Reserpine…

Mixed-acting

Answer 10

Reduced

Question 11

Tachyphalaxis

Answer 11

Rapid loss of pharmacological effect (happens faster than desensitization)