B - 5. Catecholamines

Question 1

Catecholamine names

Answer 1

epinephrine
norepinephrine
isoprenalin
dopamine

Question 2

Catecholamine synthesis

Answer 2

Phenylalanine -> tyrosine -> DOPA -> dopamine -> norepinephrine -> epinephrine

Question 3

Adrenergic receptors, class and affinity

Answer 3

a1 - NE>E - Gq
a2 - E>NE - Gi

b1 - E=NE - Gs
b2 - E»NE - Gs

Question 4

isoprenalin

Answer 4

Selective beta receptor agonist

• positive inotropic and chronotropic actions of heart
• vasodialation, decreases blood pressure
• bronchodialation

Question 5

Dopamine

Answer 5

Activates D1 receptor in low doses -> vasodialation (especially in renal area)
- can be used to protect kidney

loses selectivity in high doses; acts as epinephrine

used in cardiogenic shock

Question 6

Selective beta1 agonists

Answer 6

Dopamine (in medium doses)

Dobutamine

Question 7

Beta receptors

Answer 7

b1 -> increase HR -> increase stroke volume, CO and systolic BP
b2 -> vasodialate and decrease TPR -> decreases diastolic BP

Question 8

Dobutamine

Answer 8

• acute management of CHF -> increases CO
• doesn’t protect kidney
• tolerance limits usefulness