Brainscape's Knowledge GenomeTM

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


See full index

Cardio/Pulm Final > Lecture 15: Regulation of Arterial Pressure > Flashcards

Lecture 15: Regulation of Arterial Pressure Flashcards

1
Q

When metabolic demand is high, more blood is released through capillary beds by doing what to the arterioles?

A

Reducing resistance = Vasodilation

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

What are the 2 general methods of control for arterial pressure?

A

1) Rapid, neuronally mediated

2) Slower, hormonally mediated

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

The neuronally mediated mechanism for controlling arterial pressure relies on what?

A

Pressure sensors, a control center and pressure control mechanism influencing the heart and vasculature (baroreceptor reflex)

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

What organ is most involved in the hormonally mediated mechanism for control of arterial pressure?

A

A large component of both the sensor and pressure influencing organs are the kidneys.

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

The baroreceptor reflex utilizes?

A

Classical reflex arc

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

What are the 2 types of receptors used by the baroreceptor reflex?

A

1) Mechanoreceptors - change in pressure

2) Chemoreceptors - change in PO2, PCO2, pH

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

How quick can these detectors act and how long can they last?

A

Can act within seconds and last indefinetely

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

How do the detectors sense change in pressure?

A

Through stretch receptors on vessel wall

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

Increased stretch causes; decreases stretch casuses?

A

Increased stretch = increased firing rate

Decreases stretch = decreased firing rate

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

The carotid sinus baroreceptors are innervated by?

A

Sinus nerve of Hering, a branch of the Glossopharyngeal nerve (CN IX)

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

The aortic sinus baroreceptors are innervated by?

A

Aortic nerve, a branch of the Vagus nerve (CN X)

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

The afferent neurons of the carotid and aortic sinus travel where?

A

Up the spinal cord, to the brain stem, and finally to the nucleus tractus solitarius (NTS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the NT used by affernet neurons the NTS?

A

Glutamate

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

The rostral ventrolateral medulla is responsible for?

A

Vasculature repsonse

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

The dorsal motor nucleus of the vagus and nucleus ambiguous is responsible for?

A

Cardiac response

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

Baroreceptors send signals to the medulla, which is considered the?

A

Control center

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Stretch of receptors decreases firing rate of which neurons?

A

Afferent neurons - send the signal to the medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Efferents are both?

A

Parasympathetic (vagus) and sympathetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What parts of the brain do the afferents travel to?

A

Cerebral cortex and hypothalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Mean arterial blood pressure (MABP) =

A

HR x SV x TPR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the baroreceptor reflex working to maintain?

A

MABP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

TPR is dependent on?

A

Sympathetic stimulation of arterioles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

SV is dependent on?

A
  • Sympathetic stimulation of heart

- Preload

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

HR is dependent on?

A
  • Sympathetic (increases)

- Parasympathetic (decreases)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Increased frequency of stimulation increases what?

A

Strength of AP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How is the aortic sinus different from the carotid?

A
  • Higher threshold for activation
  • Continues to respond above saturation
  • Less sensitive to rate, less effected by decreases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

The increase or decrease in firing rate of these receptor neurons is proportional to?

A

The change in pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How does the sympathetic nervous system affect the firing rate of baroreceptors?

A

Decreases firing rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Sympathetic NS does what to arterioles and veins; via which receptor?

A

Constriction via α receptors

30
Q

Sympathetic NS does what to HR and contractility; via which receptor?

A

Increases via β receptors

31
Q

Parasympathetic NS affects the firing rate of baroreceptors how?

A

Increases firing rate

32
Q

Which nerve is part of the parasympathetic NS and signals to the SA node, atria and ventricles; via what receptor?

A

Vagus nerve using muscarinic receptors

33
Q

What is the affect of the parasympathetic NS on blood vessels?

A

Indirect vasodilation (via stimulation of NO release)

34
Q

How does HTN affect baroreceptors?

A

Will cause them to adjust their set-point to the new condition. Makes it so that the body can still respond to changes.

35
Q

How does RAAS help control BP?

A

Regulation blood volume

36
Q

For longer term adjustments to changes in BP what kind of response is invoked?

A

A hormonal response

37
Q

The hormonal response is invoked and begins how quick and building for how long?

A

Begins within minutes and can build over a period of days or longer if needed

38
Q

Renin is secreted by, in response to?

A

Secreted by the kidney in a response to a drop in BP and by sympathetic stimulation

39
Q

Stimulation of what receptor also increases the release of renin?

A

β1-adrenergic receptor by sympathetic NS

40
Q

What does renin do in the blood?

A

Causes Angiotensinogen to be converted to Angiotensin I (inactive)

41
Q

What must occur to angiotensin I to become active; where?

A

Must be converted to Angiotensin II in the lungs (and kidneys)

42
Q

What part of the kidney secretes Renin?

A

Juxtaglomerular (JG) cells in walls of renal afferent arterioles

43
Q

Angiotensin II causes the secretion of what 2 things?

A

1) Aldosterone from the adrenal cortex

2) ADH (Vasopressin)

44
Q

What does aldosterone do?

A

Leads to Na+ and H2O retention by kidney

45
Q

Aldosterone causes an increase in?

A

Blood volume, preload/stroke volume, CO, and therefore BP

46
Q

What is the affect of ADH (vasopressin)?

A

Reduces urine production (fluid retention) and increases TPR

47
Q

How does angiotensin II affect arterioles; binds to?

A

Binds to AT1 receptors and causes global vasoconstriction of arterioles

48
Q

Angiotensin II affect on the hypothalamus?

A

Increases thirst

49
Q

What do ACE inhibitors do?

A

Prevent the conversion of angiotensin I to angiotensin II in lungs

50
Q

Side effect of ACE inhibitors?

A

Cough because of a buildup of bradykinin (Angiotensin II breaks down bradykinin)

51
Q

How can arteriolar angiotensin II receptors be blocked pharmacologically?

A

Using angiotensin receptor blockers (ARBs)

52
Q

BP =

A

BP = CO x TPR

*CO = SV x HR

53
Q

Vasopressin (ADH) acts via which receptors, found where?

A

V1 receptors (smooth muscle) - increase TPR

V2 receptors (collecting ducts) - fluid retention

54
Q

Vasopressin (ADH) is secreted in response to what 3 things?

A

1) Angiotensin II
2) Increased osmolarity of blood
3) Atrial receptors in presence of low preload

55
Q

What are the 3 forms of natriuretic peptides?

A

1) Atrial (ANP)
2) Brain (BNP)
3) C-type (CNP)

56
Q

When are natriuretic peptides secreted?

A

During excessive preload of atria and ventricles

57
Q

What 3 things do natriuretic peptides cause?

A

1) Arteriolar dilation - decreases TPR
2) Increase fluid loss - decreases preload
3) Inhibits renin - decreases both TPR and preload

58
Q

Natriuretic peptides protect against?

A

Overdilation and overstretching of cardiac chambers

59
Q

Cerebral ischemia causes?

A

Increased sympathetic outflow from vasomotor center

60
Q

Why would you want increased sympathetic outflow during cerebral ischemia?

A

Sympathetic outflow = vasoconstriction = protective if BP is dropping and there will not be enough to adequately perfuse the brain

61
Q

Cushing reflex is in response to?

A

Increased intracranial pressure - compresses cerebral arteries and reduces perfusion

62
Q

What is the triad for the Cushing Reflex; cause for each?

A

1) HTN (sympathetic drive to increase blood flow to brain)
2) Bradycardia (baroreceptors sensing increased BP)
3) Irregular respiration (impaired brain stem function)

63
Q

In response to increased blood volume - increased preload, what 4 things occur?

A

1) Increases secretion of ANP
2) Decrease ADH secretion
3) Renal vasodilation
4) Increased HR

64
Q

Anticipation at what part of the brain causes the changes before exercise?

A

Cerebral cortex - central command response

65
Q

What is the central command response to the anticipation of exercise?

A

1) Increased sympathetic output/decreased parasympathetic
2) Increased HR/contractility/stroke volume
3) Increased venous return (preload)
4) Vasoconstriction (slight increase in MAP)

66
Q

What orchestrates the peripheral response (local) in exercising skeletal muscle; importance?

A
  • Active hyperemia due to an increase in local metabolites (K+, lactate, and adenosine)
  • Most important mechanism of control during exercise
67
Q

The central command during exercise causes vasoconstriction of?

A

Splanchnic (gut) and renal arterioles

68
Q

What 2 things causes an increase in venous return during exercise?

A

1) Contraction of skeletal muscle around the veins has a mechanical (squeezing) action

2) Activation of the sympathetic nervous system
produces venoconstriction.

69
Q

What triggers the anticipatory affect produced by the central command before exercise?

A

Triggered by muscle mechanoreceptors

70
Q

Vasoconstriction will not occur where during exercise?

A

Skeletal muscle, coronary and cerebral circulation

71
Q

What happens to TPR during exercise?

A

An overall decrease in TPR due to vasodilation of skeletal muscle

Cardio/Pulm Final (18 decks)

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