Week 4 - Control Of Blood Pressure

Question 1

How do you calculate mean arterial blood pressure?

Answer 1

CO X TPR

Question 2

How do you calculate cardiac output?

Answer 2

SV X HR

Question 3

What regulates blood pressure in the short term?

Answer 3

Baroreceptors

Question 4

How do baroreceptors control blood pressure?

Answer 4

Adjust the sympathetic and parasympathetic inputs to the heart to alter cardiac output, adjust sympathetic input to peripheral resistance vessels to alter TPR

Question 5

How do baroreceptors detect changes in blood pressure?

Answer 5

Nerve endings in carotid sinus and arch of aorta are sensitive to stretch, increased arterial pressure stretches them, decrease in pressure causes less stretch

Question 6

Are baroreceptors useful in sustained changes to blood pressure?

Answer 6

No because if there are long term changes the threshold for the baroreceptors firing resets at this new level

Question 7

What are the long term controls of blood pressure?

Answer 7

Neurohumoral responses, controlling sodium balance and therefore extracellular fluid, plasma is part of extracellular fluid and therefore controls the volume of blood

Question 8

What are the neurohumoral pathways controlling circulating volume and blood pressure?

Answer 8

Renin-angiotensin-aldosterone system, sympathetic nervous system, antidiuretic hormone, atrial natriuretic peptide