2. DSA Adrenergic Drugs Flashcards
Adrenergic Drugs modulate adrenergic transmission and primarily control the function of the?
sympathetic nervous system, by mimicing the effects of NE/E/Dopamine at the adrenergic receptors in the symp. NS
Types of Adrenergic Receptors: List the effect A1 (ABD) type uses Gq A2 (ABC) type uses Gi B (123) type uses Gs D1/5 uses Gs D2/3/4 uses Gi
A1 (ABD) type uses Gq- increases IP3 and DAG A2 (ABC) type uses Gi- decreases cAMP B (123) type uses Gs- Increases cAMP D1/5 uses Gs- Inc. cAMP D2/3/4 uses Gi- Dec cAMP
activation of a1 receptor leads to what chain of responses?
Gq activated, makes GDP to GTP, activates PLC, activates PIP2, DAG, IP3, DAG activates PKc and IP3 releases Ca to activate a protein kinase
activation of beta-agonists leads to what chain of responses?
Gs activated, GDP to GTP, activates adenyly cyclase, increases cAMP, which activates R2C2 (PKA)
activation of a2 receptor leads to what chain of responses?
inhibition of AC, decrease cAMP, decrease PKA
Direct-acting adrenergic drugs produce their effects via direct interaction with adrenergic receptors while indirect do what?
produce their effects by increasing or reducing the concentration of NE at target receptors (alter NT concentrations at target site)
Classify the following direct adrenomimetics
Phenylphrine
Clonidine
Alpha agonists
Phenylphrine A1>A2
Clonidine A2>A1
Classify the following direct adrenomimetics
Norepinephrine (levophed)
Epinephrine (adernalin)
Mixed alpha and beta agonists
a1=a2,B1>B2
a1=a2, b1=b2
Classify the following direct adrenomimetics
Dobutamine (Dobutrex)
Isoproterenol (Isuprel)
Albuterol (ventolin)
Beta Agonists
b1>b2
B1=b2
b2>b1
Classify the following direct adrenomimetics
Dopamine (Intropin)
Dopamine agonists
D1=D2
What endogenous catecholamine does the following?
Effects of cardiac function (b1) increases
Effects on vascular tone (B2 and A1) increases
Skin vessels via A1
Skeletal muscle via A1/B2
Renal/Cerebral D1 and A1
Effects on respiratory system, etc
Epinephrine
What endogenous catecholamine does the following?
a1=a2,b1>b2
Reduces heart rate
vasoconstrictor
lacks b2 agonist - no bronchodilation/vasodilation
increase peripheral vascular resistance and BP
Role of baroreflex
Norepinephrine
What alpha adrenergic does the following (a1)?
Mydriatic and decongestant
severe vasoconstriction, BP elevation and severe bradycardia
Phenylphrine - a1>a2
What alpha adrenergic does the following (a2)?
a2 in lower brainstem: decreases sympathetic outflow, reduces BP, bradycardia
Local application results in vasoconstriction
regulation of NE release by presynaptic receptors
Clonidine - selective A2>a1
What beta adrenergic does the following (b1=b2)?
non-selective
positive inotropic and chronotropic action, inc. CO (b1)
Vasodilator, dec. arterial pressure B2
Causes bronchodilation B2
Isoproterenol
What beta adrenergic does the following (b1>b2)?
Selective b1
(-) isomer is agonist at a1, (+) isomer is antagonist at a1
potent inotropic action
less prominent chronotropic
Dobutamine
What beta adrenergic does the following (b2>b1)?
selective b2
Cause bronchodilation and relaxation of uterus
Albuterol
What endogenous catecholamine does the following?
D1 stimulation causes vasodilation (renal, cerebral, mesenteric have high density)
Activation of presynaptic D2- supress NE release
Activated B1 in heart at high doses
At higher doses stimulates vascular a1 AR to cause vasoconstriction
Dopamine
Cocaine is an indirect adenergic agonist (indirect sympathomimetic) whats it’s MOA?
inhibits re-uptake of DA and NE
Phenelzine/Selegiline is an indirect adenergic agonist (indirect sympathomimetic) whats it’s MOA?
inhibits MAO
Amphetamine/Methylphenidate is an indirect adenergic agonist (indirect sympathomimetic) whats it’s MOA?
Inhibit re-uptake of DA/NE, increases their release, may have weak direct effect
Ephedrine is an indirect adenergic agonist (indirect sympathomimetic) whats it’s MOA?
releasing agent and direct adrenergic receptor agonist
Indirect adrenergic agonists are more lipophilic, and easily penetrate the BBB. What drug has the following effects?
Simulant effect on mood/alertness
decreases appetite
Drugs of abuse
Amphetamine