Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Principles Physiology > Long-term regulation of MAP > Flashcards

Long-term regulation of MAP Flashcards

1
Q

Why does the pressure in large arteries remain relatively high compared to other blood vessels?

A

They contain lots of elastic fibres which recoil during diastole meaning there is still some pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What valve helps keep the diastolic pressure above zero in the arteries.

A

Intact aortic valve.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which 3 types of hormones/pathways act as effectors for long-term regulation of MAP?

A
  • The renin-angiotensin-aldosterone system (RAAS)
  • Natriuretic peptides (NPs)
  • Antidiuretic hormones (ADH)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What portion of the total body fluid is taken up by extracellular fluid?

A

1/3.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is equation for Extracellular volume (ECFV)?

A

ECFV= Plasma volume (PV) + Interstitial fluid volume (IFV)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is interstitial fluid?

A

The fluid which bathes cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What compensatory mechanism happens when plasma volume drops? (hint: interstitial fluid)

A

Compensatory mechanisms shifts fluid from the interstitial compartment to the plasma compartment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Blood volume and MAP is regulated if ECFV is regulated. True or false?

A

True.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What two main factors affect extracellular fluid volume?

A

Water and Na+ excess or deficit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the three hormones of the RAAS?

A

Renin, angiotensin and aldosterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does RAAS regulate?

A

Plasma volume and SVR, hence regulating MAP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the pathway of RAAS.

A
  1. Renin is released from granular cells in juxtaglomerular apparatus in kidneys
  2. stimulating formation of angiotensin I in blood from angiotensinogen
  3. Angiotensin I is converted to Angiotensin II by the enzyme called angiotensin converting enzyme (ACE) produced by pulmonary vascular endothelium
  4. Angiotensin II stimulates the release of aldosterone from the adrenal cortex
  5. Angiotensin II causes systemic vasoconstriction, increasing SVR. Also stimulates thirst and ADH release which contributes to increasing plasma volume
  6. Aldosterone (a steroid hormone) acts on the kidneys to increase sodium and water retention- increases plasma volume.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where is renin released from?

A

From granular cells in juxtaglomerular apparatus in kidneys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What regulates the RAAS?

A

By mechanisms which stimulate the Renin release:

  • renal artery hypotension.
  • stimulation of renal sympathetic nerves
  • decreased [Na+] in renal tubular fluid.

Decreasing renin release decreases blood pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the rate limiting step for RAAS?

A

The Renin secretion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are natriuretic peptides?

A

Peptide hormones synthesised mainly by the heart (also by brain and other organs)

17
Q

What do natriuretic peptides do?

A

Act as vasodilators and cause excretion of salt and water in kidneys, which reduces the blood plasma volume and blood pressure.

18
Q

Which two hormone pathways are counter-regulatory to one another?

A

RAAS and natriuretic peptides

19
Q

What are the two types of natriuretic peptides?

A

Arterial natriuretic peptide (ANP)- made and stored in atrial muscle cells, released in response to atrial distension

Brain-type natriuretic peptide (BNP)- synthesised by heart ventricles, brain and other organ, also released in response to
volume expansion and increased wall stress of cardiac myocytes

20
Q

Which form of natriuretic peptides is used to detect suspected heart failure in patients?

A

BNP.

21
Q

What is plasma osmolality?

A

The measure of solute-water balance.

22
Q

What stimulates ADH release?

A

Increased (or decreased) plasma osmolality /extracellular fluid volume

23
Q

What is plasma osmolality monitored by?

A

osmoreceptors mainly in the brain in close proximity to the hypothalamus

24
Q

What are antidiuretic hormones (ADH)?

A

peptide hormones derived from pro-hormone precursors synthesised by the hypothalamus and stored in the posterior pituitary.

25
Q

How does ADH regulate the plasma osmolality?

A

it acts in kidney tubules to increase the reabsorption of water, increasing the extracellular and plasma volume and hence cardiac output and blood pressure.

26
Q

What is ADH also known as?

A

Vasopressin

27
Q

ADH cannot act on blood vessels to cause vasoconstriction. True or false?

A

False.

Principles Physiology (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions