Direct Adrenergic Agonist Drugs

Question 1

effect of epinephrine on cardiac function (B1 receptors)

Answer 1

• increases force of heart contraction (increase inotropy)
• increase HR
• increase conduction velocity at AV node

Question 2

effect of epinephrine on vascular tone (B2 and A1 receptors)

Answer 2

• increase systolic BP

- may decrease diastolic BP and PVR

Question 3

effect of epinephrine on respiratory system

Answer 3

• relaxes bronchial muscle (B2)

- decreases bronchial secretion and congestion within bronchial mucosa (a1)

Question 4

effect of epinephrine on skeletal muscle

Answer 4

• muscle tremors (B2)

- increases K+ uptake by skeletal muscle (B2)

Question 5

effect of epinephrine on blood glucose levels (B2)

Answer 5

enhances liver glycogenolysis and gluconeogenesis

Question 6

effect of epinephrine on blood free fatty levels (B receptors)

Answer 6

increases

Question 7

effect of epinephrine on renin release (B1)

Answer 7

increases

Question 8

effect of NE on cardiac function

Answer 8

• cardiac stimulator, but reduces heart rate

Question 9

effect of NE on bronchodilation and vasodilation

Answer 9

NO effect - NE lacks B2 agonist effects

Question 10

effect of NE on PVR and BP

Answer 10

increases them

Question 11

effect of NE on vasoconstriction/dilation

Answer 11

potent vasoconstrictor

Question 12

what receptors does NE affect

Answer 12

• a1 = a2

- B1&raquo_space; B2

Question 13

what receptors does phenylephrine affect

Answer 13

a1 > a2&raquo_space;»> B

alpha agonist

Question 14

effect of phenylephrine on cardiac function

Answer 14

• increase BP

- severe bradycardia

Question 15

effect of phenylephrine on vasoconstriction/dilation

Answer 15

severe vasoconstriction

Question 16

what receptors does clonidine affect

Answer 16

a2 > a1&raquo_space;»> B

selective a2 agonist

Question 17

effect of clonidine on sympathetic outflow

Answer 17

decreases it

Question 18

effect of clonidine on cardiac function

Answer 18

• reduces BP

- bradycardia

Question 19

local application of clonidine causes ___

Answer 19

vasoconstriction

Question 20

effect of clonidine on NE release

Answer 20

regulates it via presynaptic a2 adrenoceptors

decreases its release accordingly

Question 21

what receptors does isoproterenol affect

Answer 21

B1 = B2&raquo_space;» a

non-selective beta agonist

Question 22

effect of isoproterenol on cardiac function

Answer 22

• positive inotropic and chronotropic action

- increases CO (B1)

Question 23

effect of isoproterenol on vasoconstriction/dilation and arterial pressure

Answer 23

• vasodilator

- decreases arterial pressure (B2)

Question 24

effect of isoproterenol on respiratory function

Answer 24

causes bronchodilation (B2)

Question 25

what receptors does dobutamine affect

Answer 25

B1 > B2, alpha1 | selective B1 agonist with some alpha1 activity

Question 26

describe the alpha 1 activity of dobutamine

Answer 26

(-) isomer is an agonist while (+) isomer is an antagonist

Question 27

effect of dobutamine on cardiac function

Answer 27

- potent inotropic action | - less prominent chronotropic action compared to isoproterenol

Question 28

what receptors does albuterol affect

Answer 28

B2 > B1 >>>> alpha | selective B2 agonist

Question 29

effects of albuterol on respiratory function

Answer 29

bronchodilation

Question 30

effects of albuterol on uterus

Answer 30

relaxes it

Question 31

what receptors does dopamine affect

Answer 31

D1 = D2 >> B1 >> a1

Question 32

effect of dopamine on D1 receptor

Answer 32

vasodilation

Question 33

effect of dopamine on presynaptic D2 receptor

Answer 33

suppresses NE release

Question 34

effect of dopamine on cardiac function

Answer 34

activates B1 receptor in heart (at higher doses) | - increase force and rate of contraction

Question 35

effect of dopamine on vasoconstriction/dilation

Answer 35

stimulates vascular a1 receptors to cause vasoconstriction (at higher doses)