blood vessels

Question 1

Blood Pressure = ?

Answer 1

Cardiac output x peripheral resistance

Question 2

What are the factors that influences cardiac output?

Answer 2

Blood volume: sodium, mineralcorticoids, atriopeptin

Cardiac factors: heart rate, contractility

Question 3

What are the factors that influences peripheral resistance?

Answer 3

Humoral factors:
constrictors = Angiotensin II, catecholamines, thromboxane, leukotrienes, endothelin
dilators = prostaglandins, kinins, NO

Local factors
Autoregulation, Ionic (pH, hypoxia)

Neural factors
constrictors = a-adrenergic
dilators = b-adrenergic

Question 4

Important mediators in bp regulation?

Answer 4

1) Renin –
2) Angiotensin –
3) Angiotensin-converting enzyme (ACE) –
4) Prostaglandins –
5) Nitric oxide (NO) –
6) Adrenal aldosterone –
7) Myocardial natriuretic peptides –

Question 5

Hypertension is an important risk factor for which conditions?

Answer 5

Ischemic heart disease
Cerebrovascular accident (stroke)
Congestive heart failure
Renal failure

Question 6

Hypertension mechanisms?

Answer 6

2) Reduced Renal Sodium Excretion
a) Increases renal fluid retention, thus increasing blood volume and cardiac output.

3) Increased Vascular Resistance
a) Chronic vasoconstriction
b) Permanent thickening of blood vessel walls

4) Genetic Factors
a) Polymorphisms for angiotensin and/or angiotensin II receptors
b) Susceptibility genes for renal sodium regulation, pressors, smooth muscle cell growth

5) Environmental Influences (modifiable)
a) Stress (cortisol, catecholamines)
b) Obesity (affects blood viscosity)
c) Smoking
d) Inactivity
e) High consumption of salt