(12) Regulation of Arterial Pressure (Rogers)

Question 1

What is the equation for mean arterial pressure?

***

Answer 1

MAP = CO x TPR = HR x SV x TPR

Question 2

What is the normal mean arterial pressure value?

Answer 2

Normally 93.3 mmHg (around 100 mmHg)

Question 3

Where are the two primary baroreceptors?

Answer 3

Carotid Sinus

Aortic Sinus

Question 4

Where does the baroreceptor reflex travel up toward?

Answer 4

Nucleus tractus solitarius (NTS)

Question 5

Mechanoreceptors respond to…

Answer 5

Changes in arterial pressure

Question 6

Chemoreceptors respond to…

Answer 6

PO2, PCO2, pH

Question 7

Baroreceptors will ______ firing rate in response to increased stretch

Answer 7

Increase

Question 8

Baroreceptors will ______ firing rate in response to pressure dropping

Answer 8

Decrease

Question 9

Role of nucleus of tractus solitarius (NTS)?

Answer 9

Receives and coordinates peripheral signals

Question 10

Rostral ventrolateral medulla has __________ activiy with CV function

Answer 10

Sympathetic

Question 11

Dorsal motor nucleus of the vaus and nucleus ambiguus has __________ activiy with CV function

Answer 11

Parasympathetic

Question 12

TPR is heavily dependent on __________

Answer 12

Sympathetic stimulation of arterioles

Question 13

Equation for CO?

Answer 13

CO = SV x HR

Question 14

Sympathetic nervous system causes:

Answer 14

• Decreased baroreceptor firing rate
• Contriction of arterioles and veins (alpha receptors)
• Incrases HR and contractility (B1 receptors)
• Fluid retention by kidney

Question 15

Parasympathetic nervous system causes:

Answer 15

• Increased baroreceptor firing rate
• Decreased HR (vagus nerve to SA node)
• Indirect vasodilation on blood vessels (e.g., stimulate NO release)

Question 16

Draw the flow chart for Decreased MAP effects

Answer 16

Decreased MAP, need to INCREASE arterial pressure

Question 17

Draw the flow chart for INCREASED MAP

Answer 17

Need to DECREASE arterial pressure

Question 18

What happens to baroreceptors with people that have high blood pressure?

Answer 18

Able to adjust set-point to different conditions:

Hypertension is classic example

Question 19

What is the RAAS system?

Answer 19

Renin- Angiotensin II - Aldosterone System

Question 20

Function of RAAS system?

Answer 20

For long term adjustments in blood pressure by regulating blood volume:

Produces a hormonal response

Question 21

What is Renin?

What is the release stimulated by?

Answer 21

Enzyme secreted by the kidney into the bloodstream in response to a drop in BP

B1-adrenergic receptor activation

Question 22

Biochemically, what does Renin do?

Answer 22

Causes Angiotensinogen to be converted to Angiotensin I in the blood

Later on…

Angiotensin I is converted to antiotensin II in the lungs and kidneys to begin the compensation mechanism

Question 23

What type of cells secrete renin?

Answer 23

Juxtaglomerular (JG) cells

Question 24

Angiotensin II causes

Answer 24

1) Secretion of aldosterone from adrenal cortex –> leads to increased Na+ and H2O retention by kidney = Increased blood volume, preload/SV, CO and therefore BP!!!!
2) Secretion of ADH
3) Vasocontriction

Question 25

Describe the RAAS system in flow chart

Answer 25

Question 26

Vasopressin (ADH) acts at ____ and ____ receptors

Answer 26

V1 (smooth muscle) V2 (colellecting ducts)

Question 27

Vasopressin (ADH) is secreted in response to...

Answer 27

Angiotensin II Artial receptors (low preload) Increased osmolarity of blood

Question 28

Function of ADH?

Answer 28

Increase TPR and water retention

Question 29

What are the three types of **natruiuretic peptide?**

Answer 29

Atrial (ANP) Brain (BNP) C-type (CNP)

Question 30

Function of **natriuretic peptides?**

Answer 30

Prevent overstretching the chambers of the heart

Question 31

Describe what happens in response to a **hemorrhage**

Answer 31

Question 32

This will be a test question: He loves exercise, said put a flag on this: Describe the exercise response flow chart

Answer 32

Question 33

Firing: What happens with: Decreased pressure = Increased pressure =

Answer 33

Decreased pressure = Firing rate goes down Increased pressure = Firing rate goes up