Chapter 9: Regulation of Arterial Pressure

Question 1

Where are the baroreceptors located and how do they function?

Answer 1

aortic arch
carotid sinus

mechanoreceptors-receptors –> stretched –> inhibitory impulse to the brain stem –> reducing sympathetic tone

Question 2

What are the two factors that influence the baroreceptors?

Answer 2

MAP
Pulse pressure (also activated by degree of change)

Question 3

Why are baroreceptors not sufficient for long term BP regulation?

Answer 3

• lose their sensitivity/activity after long term stretch i.e., adapt to long-term change

Question 4

What nerves do each of the baroreceptors signal to?

Answer 4

aortic arch –> vagus
carotid sinus –> carotid sinus nerve (Hering nerve) –> glossopharyngeal

Question 5

What are the 3 effects caused by activated baroreceptors? (if BP is increased)

Answer 5

• inhibit spinal sympathetic excitatory tract
• stimulate activity of spinal sympathetic inhibitory tract
• stimulate activity of parasympathetic preganglionic nerves

Question 6

Where are the cardiopulmonary receptors located?

Answer 6

atria
ventricles
coronary vessels
lungs

Question 7

Where are the peripheral and central chemoreceptors located and what do they sense?

Answer 7

peripheral:
aortic bodies
carotid bodies
* sense pH, CO2, O2

central:
brain
* sense CO2 through pH

Question 8

How does a carotid massage work?

Answer 8

pressure applied to the neck –> aims to cause activation by direct pressure, simulating increased blood pressure –> increased parasympathetic and decreased sympathetic tone –> decrease HR

Question 9

How does superficial/cutaneous and deep/visceral pain differ in their effect on the cardiovascular system?

Answer 9

superficial/cutaneous –> increased BP

visceral/deep –> drop in BP

Question 10

How does the sympathetic nervous system affect renin release?

Answer 10

• direct receptors to induce renin release (beta-1 adrenergic mechanisms)
• arteriolar vasoconstriction –> decreased GFR –> renin release