Adrenergic Agonist- T1

Question 1

alpha1- adrenergic selective agonist

Answer 1

phenylephrine

Question 2

alpha2- adrenergic selective agonist

Answer 2

• clonidine
• brimonidine
• tizanidine
• alpha-methyldopa

Question 3

sympathomimetic amines (4)

Answer 3

• addy
• methylphen
• focalin
• vyvanse

Question 4

alpha adrenergic (subtype non-selective)

Answer 4

• oxymetazoline–> afrin

- naphazoline–> visine

Question 5

beta2- adrenergic selective agonist

Answer 5

• albuterol
• salmeterol–> advair
• Levalbuterol

Question 6

sympathetic potency at alpha receptor

Answer 6

epi>norepi> isoproterenol

Question 7

sympathetic potency at beta receptor

Answer 7

isoproterenol > epi > norepi

Question 8

alpha receptors tend to

Answer 8

restrict

Question 9

beta receptors tend to

Answer 9

relax, except at the heart where they constrict the cardiac muscle.

Question 10

signal transduction for beta-adrenoceptor: beta receptors are coupled to…

Answer 10

adenylyl cyclase activation–> increase in cAMP helps to mediate cardiac cells

Question 11

signal transduction for beta-adrenoceptor: alpha2 receptors are…

Answer 11

inhibitory on beta receptors if they are found in the same location. coupled to GI and tend to inhibit adenylyl cyclase synthesis. act like muscarinic M2 receptor which oppose beta receptors and slow HR by not allowing cAMP to be produced.

Question 12

beta-adrenoceptor regulation of cardiac chronotropy (HR) and isotropy(contraction): PKA-

Answer 12

phosphorylates voltage-dependent Ca channel and the SR Ca-ATPase. calcium influx and depolarization which increases constriction and HR. Sarcoplasm Ca-ATPase increases calcium storage. Ca coming in from the outside is a trigger for Ca release from the SR.

Question 13

beta-adrenoceptor regulation of smooth muscle relaxation. PKA phosphorylates

Answer 13

plasma membrane and Sr-Ca-ATPase to decrease inctracellular Ca.

Question 14

signaling system for alpha1-adrenoceptor mediated effects

Answer 14

phosphoinositide hydrolysis and Ca mobilization. when you get more IP3, you get more Ca, which results in increase contraction.

Question 15

mobilization of intracellular Ca in smooth muscle: contraction via activation of MLCK

Answer 15

ca released in sooth muscle binds to calmodulin and then the calmodulin activates MLCK.

Question 16

MLCK phosphorylates…

Answer 16

light chain of myosin heads and increases affinity of myosin for actin once it phosphorylates myosin head.

Question 17

mobilization of intracellular Ca in smooth muscle: alpha2 adrenoceptor in vascular smooth muscle may use coupling to

Answer 17

ROCs to produce smooth muscle contraction:

-presynaptically, alpha receptors are inhibitory and don’t allow norepi release.

Question 18

effect of adrenergic agonist on cardiac parameters: phenylephrine

Answer 18

infusion of phenylephrine produces vasoconstriction and reflex decrease in HR. has affinity for alpha1 receptors. increase in MBP and decrease HR

Question 19

effect of adrenergic agonist on cardiac parameters: isoproterenol

Answer 19

infusion of isoproterenol produces dramatic vasodilation and increase in HR with decrease in BP. affinity for beta receptors and decrease in MBP and increase in HR

Question 20

effect of adrenergic agonist on cardiac parameters: epi

Answer 20

slow infusion of epi results in vasodilation and increase HR with little change in MBP. has affinity for alpha and beta receptors.

Question 21

oxymetazoline is what receptor selective

Answer 21

alpha receptor selective. but doesn’t select between alpha subtypes.

Question 22

brimonidine is a

Answer 22

alpha2 adrenergic agonist for open angle glaucoma. beta2 receptor increases aq humor and alpha2 receptor decreases aq humor.