CV Centres & CV Innervation

Question 1

What are the 3 cardiovascular centres?

Answer 1

Cardioacceleratory (SNS)
Cardioinhibitory (PNS)
Vasomotor (SNS)

Question 2

Where are the CV centres located?

Answer 2

In the medulla oblongata (regulatory region)

Question 3

Where do the CV centres receive their information from?

Answer 3

Visceral afferent fibres (CNIX and CNX - via the solitary nucleus)

Hypothalamus
Limbic system
Cerebral cortex

Question 4

What are the actions of the cardioacceleratory centre?

Answer 4

Increase HR and BP by:

activating B1 receptors in SA node and myocardium (via cardiopulmonary splanchnic nerves)

• increase HR (SA node)
• increase contractility (myocardium)

Question 5

What are the actions of the cardioinhibitory centre?

Answer 5

Lower HR and BP by:

activating M2 receptors in the SA node and myocardium (CNX via dorsal motor nucleus of X)

• decrease HR (SA node)
• decrease contractility (myocardium)

Question 6

What are the actions of the vasomotor centre?

Answer 6

Increase TPR and BP by:

activating A1 receptors in tunica media of blood vessels

• increases TPR and BP