Neurohumoral, Local and Volumetric Cardiovasular Control I & 2

Question 1

What is a neurohormone?

Answer 1

Any hormone produced by neuroendocrine cells

Question 2

What effect does oxytocin have?

Answer 2

Hypotensive effects

Question 3

What is vasopressins affect?

Answer 3

Vasoconstricts and causes water reabsorption by kidneys

Question 4

What does ANP (atrial natriuretic factor) do?

Answer 4

Causes the kidneys to output more sodium and water follows to decrease blood volume

Question 5

What cells produce epinephrine and norepinephrine?

Answer 5

Chromafin cells in the adrenal medulla

Question 6

What is a pheochromocytoma?

Answer 6

A catecholamine producing tumor which may cause paroxysmal hypertension

Question 7

What is the effect of epinephrine in low concentration?

Answer 7

Vasodilatory

Question 8

What is the effect of epinephrine in high concentration?

Answer 8

Beta adrenergic cardiac effects

Question 9

What is the main controller of vascular smooth muscle tone?

Answer 9

Norepinephrine through alpha adrenergic receptors

Question 10

What is the effect of dopamine?

Answer 10

Increases arterial pressure and heart rate

Question 11

What type of receptors do catecholamines work on?

Answer 11

G protein-coupled receptors

Question 12

What effect does serotonin (5-HT) have on vessels?

Answer 12

Vasoconstriction

Question 13

What effect does histamine have on vessels?

Answer 13

Vasodilation

Question 14

What does angiotensin II do?

Answer 14

Regulates renal sodium reabsorption and potassium excretion and vasoconstricts

Question 15

What does aldosterone do?

Answer 15

Acts on distal renal tubule and collecting ducts, increasing Na+ reabsorption and K+ excretion; increasing blood volume

Question 16

What is primary hyperaldosteronism?

Answer 16

Adrenal gland tumor hypersecretion of aldosterone and causing hypertension

Question 17

How does the renin-angiotensin-aldosterone system work?

Answer 17

Liver releases angiotensinogen in response to poor kidney perfusion; renin is excreted from kidney to cleave angiotensinogen into angiotensin I; ACE converts angiotensin I into angiotensin II; angiotensin inhibits bradykinin causing vasoconstriction and release of aldosterone from the adrenal cortex leading to sodium retention

Question 18

What affect does angiotensin II have on the brain?

Answer 18

Release of ACTH from anterior pituitary to act on the adrenal cortex

Question 19

What is the long term affect of stress on the hypothalamus?

Answer 19

Release of ACTH from hypothalamus acting on adrenal cortex to release glucocorticoids (protein and fat metabolism occur) and release of mineralocorticoids (blood volume and pressure increase)

Question 20

What is the short term affect of stress on the hypothalamus?

Answer 20

Hypothalamus sends as impulse to the spinal cord to the adrenal medulla to release epinephrine and norepinephrine increasing HR and BP

Question 21

What do metabolites do?

Answer 21

They diffuse to vascular smooth muscle and cause relaxation (K, H, CO2, lactate, adenosine)

Question 22

What does bradykinin do?

Answer 22

Binds beta 2 receptors on endothelial cells causing NO and prostacyclin release

Question 23

What effect does ATP have on vsm?

Answer 23

Vasoconstriction

Question 24

What effect does endothelin have on vsm?

Answer 24

Vasoconstriction

Question 25

What does thromboxane do to vsm?

Answer 25

Vasoconstriction through increased Ca2+ concentration

Question 26

What is the myogenic theory of autoregulation?

Answer 26

Intrinsic contraction in response to stretch

Question 27

What is the metabolic theory of autoregulation?

Answer 27

Vasodilation is the most important mechanism of autoregulatory blood flow control

Question 28

What is autoregulation?

Answer 28

Constant flow in the face of changing driving pressure

Question 29

What do kinins and histamines do to visceral smooth muscle?

Answer 29

Cause contraction

Question 30

How do histamines increase vascular permeability?

Answer 30

Increase post capillary resistance increasing hydrostatic pressure leading to extravasation

Question 31

What is the rank order potency for vascular leakage?

Answer 31

Leukotrienes > Bradykinin > Histamine > Prostaglandins

Question 32

What promotes new vascular growth?

Answer 32

Vascular endothelial growth factor
Fibroblast growth factor
Angiopoietin 1
Angiogenin

Question 33

What inhibits new vascular growth?

Answer 33

Angiostatin
Endostatin
Angiopoietin 2