Cardiovascular Physiology Part E: Blood Pressure

Question 1

What is blood pressure?

Answer 1

hydrostatic pressure exerted by blood on wall of vessel- results when flow is opposed by resistance.

Question 2

What is systolic pressure produced by?

Answer 2

ventricular contraction against vascular resistance

Question 3

What is diastolic pressure produced by?

Answer 3

elastic arteries against vascular resistance ( when ventricles are relaxed)

Question 4

Pulse pressure equation

Answer 4

systolic - diastolic

Question 5

Blood pressure measurement in artery equation

Answer 5

systolic / diastolic

Question 6

Mean Arterial Pressure and equation

Answer 6

average BP through cardiac cycle

Cardiac Output x total peripheral resistance

Question 7

Extrinsic Regulation of MAP:

Neural Control- baroreceptor reflexes

Answer 7

short term changes
stretch receptors- monster MAP in:
-carotid sinus (brain BP)
-aortic arch (systemic BP)

Question 8

Extrinsic Regulation of MAP:

Neural Control-chemoreceptor reflexes

Answer 8

• peripheral chemoreceptors – respond to pH, CO2 (and O2)
• found in aortic arch and carotid sinus (called “bodies”)
• involved in regulation of respiration, but affect bp

Question 9

Extrinsic Regulation of MAP:

Hormonal Control- epinephrine

Answer 9

⇑ HR, force of contraction ∴ ⇑ CO ⇒ ⇑ MAP

Question 10

Extrinsic Regulation of MAP:

Hormonal Control- Renin-Angiotensin System

Answer 10

Angiotensin II causes:
-⇑ vasocon, ⇑ venocon ∴ ⇑ MAP
⇑ aldosterone, ADH ∴ ⇑ renal Na+, H2O abs; ⇑ thirst ∴ ⇑ blood vol ⇒ ⇑ MAP

Question 11

Extrinsic Regulation of MAP:

Hormonal Control- Atrial Natriuretic Peptide (ANP) causes:

Answer 11

• ⇓ renin (∴ ⇓ angio II) ⇓ aldosterone, ⇓ ADH = ⇑ urine production ∴ ⇓ blood vol
• ⇓ vasoconstriction
• so overall = ⇓ MAP