Brainscape's Knowledge GenomeTM

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


See full index

Systems: Cardiovascular > Regulation of arteriolar resistance > Flashcards

Regulation of arteriolar resistance Flashcards

1
Q

What is Darcy`s Law?

A

Flow is equal to pressure diff devided by resistance

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

What is Poiseuille`s Law?

A

Resistance is equal to viscosity by length by 8 divided by radius to the power of 4 x pi

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

What does increasing the haematocrit do?

A

Increases viscosity of blood

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

Pressure is equal to what?

A

Flow x Resistance

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

How can you apply pressure = flow x resistance to systemic circulation?

A

MAP- CVP= COx TPR

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

Why can CVP be ignored?

A

Because its so small

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

What is the average MAP?

A

90/95mmHg

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

What is the average CVP?

A

0-5mmHg

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

What happens when total peripheral resistance is reduced?

A

Mean arterial pressure is also reduced

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

Can you affect one vascular bed and not mean arterial pressure

A

NO YE GIT

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

How do you keep the blood flow to each vascular bed sufficient and keep mean arteial pressure in the right range?

A

Intrinisc mechanisms -selfish needs of each individual tissue
Extrinsic mechanisms-

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

How does the sympathetic system affect extrinsic control?

A
  • releases norepinephrine
  • binds to alpha1- receptors
  • Causes arteriolar constriction
  • Reduces flow through tissue and increases TPR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What effect does parasympathetic system have on extrinsic control?

A

NON

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

How does hormonal control affect Extrinic control?

A 
ADRENALINE
(released from adrenal medulla)
-Binds to alpha 1 receptors
-causes arteriolar consriction
-Therefore decrease flow through that tissue Increase TPR

IN SOME cases
-binds B2 receptors in skeletal and cardiac to cause arteriolar dilation

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

What effect does Angiotensin 2 have?

A

Causes arteriolar constriction

Increases TPR

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

When is angiotensin 2 produced?

A

in response to low blood volume

Long term porduced in kidney

17
Q

When is vasopressin released?

A

in response to low blood volume

18
Q

What is another name for vasopressin?

A

antidiuretic hormone

Long term porduced in kidney

19
Q

When are artial natriuretic peptide & brain natriuretic peptide released?

A

-Released in response to high blood volume

20
Q

What does artial natriuretic peptide & brain natriuretic peptide do?

A

-Causes artiolar dilation
Decreases TPR
(Long term produced in kidney)

21
Q

What does EDRF mean?

A

endothelium derived relaxing factor

22
Q

Why is EDRF released?

A

in response to metabolites from hard working tissue

23
Q

Name some of the metabolites released by hard working tissue

A
  • CO2
  • H+
  • K+
24
Q

What does EDRF cause?

A

arteriolar dialitation

25
Q

Why does EDRF cause arteriolar dilation?

A

To wash out metabolites

26
Q

How does the body respond to a decrease in MAP and flow locally?

A

Releases EDRF

27
Q

What is reactive hyperaemia

A
  • occulsion of blood (rubber band on arm) supply causes a subsequent increase in blood flow
  • (an extreme version of pressure autoreg)
28
Q

Describe the injury response?

A

C fibres pick up pain
release substance P which causes mast cells to release histamine
Increased permeability causes white cells to be allowed out

29
Q

What does histamine cause?

A

increase in blood flow

increase in permeability

30
Q

What happens when heart contracts ?

A

It cuts off its own blood supply

31
Q

How does coronary circulation cope with increased demand during exercise?

A
  • excellent hyperaemia
  • Expresses many B2 receptors
  • These swamp any sympathetic arteriolar constriction
32
Q

What type autoregulation does the cerebral circ show?

A

Excellent pressure autoregulation

33
Q

What is the main function of renal circ?

A

Filtration which depends on pressure

34
Q

What do changes in MAP have a big affect on?

A

Blood volume

35
Q

What type of auto regulation does the renal circ show?

A

Excellent pressure regulation

36
Q

What is pressure regulation?

A

EDRF released in response to MAP decreased and decreased flow

Systems: Cardiovascular (31 decks)

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