The Adrenergic Receptors in the Sympathetic Nervous System

Question 1

Epi vs. NE

Answer 1

Epi - Stronger for Betas than alphas

NE - Beta 1 more than alpha 1 or 2…alpha 1 or 2 more than beta 2

Really no affinity for B2 from NE

Question 2

Locations of beta receptors

Answer 2

1 - heart and kidney

2 - vascular and non-vascular smooth muslce

Question 3

Role of Beta 1 and physiologic consequences

Answer 3

Cardiac function regulation

Inrease force and HR

Increase renin release and angiotensin 2 formation

Question 4

Overall controls of HR

Answer 4

M2 muscarinic slows down

Beta 1 increases (if overstimulated, then arrythmias)

Question 5

Role of Beta 2 and consequences

Answer 5

Regulate vascular and non vascular smooth muscle functions

Relaxation of vascular and nonvascular smooth mucles

Mostly EPI

Question 6

Alpha 1 role and consequences

Answer 6

Regulate smooth muscle tone and blood flow

Leads to increase in blood pressure (particularly in GI and non skeletal muscle)

Question 7

Alpha 2 role and consequences

Answer 7

Regulates synpatic release of NE

Inhibits release of NE…NE can be taken up and terminates the response…on the presynaptic terminal