Nerve reflexes and control of arterial blood pressure

Question 1

The arterial pressure is determined directly by two major physical factors, what are they?

Answer 1

the arterial blood volume and the arterial compliance.

Question 2

The physical factors (arterial blood volume and arterial compliance) are affected in turn by certain physiological factors which are (blank X 4)

Answer 2

heart rate, stroke volume, cardiac output, and peripheral resistance.

Question 3

If we are able to change/regulate 
	- heart rate, 
	- stroke volume and/or 
	- vessel diameter 
we will be able to change/regulate the (blank)

Answer 3

arterial blood pressure.

Question 4

What do barorecepetors do?

Answer 4

sense changes in pressure and send message to brain to correct blood pressure back to normal

Question 5

What are the the baroreceptors called?

Answer 5

the detectors/sensor

Question 6

What are the five components of neural control system?

Answer 6

) a signal (change in arterial pressure), 2) detectors or sensors (arterial baroreceptors), 3) afferent pathways that translate the signal to a coordinating center, 4) a neural network (CNS; coordinating center), which compares a signal from the sensors with a command signal which originates in CNS, 5) a neural output which connects the nervous system to the target cells in the effector organs (efferent pathways), and 6) the target organs themselves (heart and peripheral blood vessels).

Question 7

Baroreceptors are (blank) receptors that are located within the walls of the carotid sinus near the bifurcation of the common carotid arteries.

Answer 7

stretch

Question 8

Baroreceptors are stretch receptors that are located within the walls of the (blank) near the bifurcation of the common carotid arteries.

Answer 8

carotid sinus

Question 9

The two most important high-pressure loci are the (blank) .

Answer 9

carotid sinus and the aortic arch

Question 10

The baroreceptors are the branched and coiled bare ends of (blank) nerve fibers. The cell bodies are in (blank) near the brain stem.

Answer 10

myelinated sensory

ganglia

Question 11

What do the arterial baroreceptors sense?

Answer 11

stretch (changes in blood pressure and vascular wall tension)

Question 12

The activity of the baroreceptors is increased upon sudden (blank) in blood pressure and is decreased in response to sudden decrease of blood pressure.

Answer 12

increase

Question 13

The purpose of the Arterial Baroreceptors is to (blank) ACUTE changes in blood pressure

Answer 13

buffer

Question 14

High-pressure baroreceptors respond not only to the absolute level of the blood pressure, but also to how (blank).

Answer 14

rapidly it changes

Question 15

What are the Aortic baroreceptors pressure ranges over which the aortic baroreceptors can monitor systemic arterial blood pressure?
Carotid baroreceptors?

Answer 15

100-200

50-200

Question 16

Degree of high-pressure baroreceptor stimulation is directly related to (blank)

Answer 16

magnitude and rate of change of blood pressure.

Question 17

What do the cardio-pulmonary baroreceptors sense?

Answer 17

stretch (venous return to the heart, changes in bloo volume, EDP)

Question 18

Low-pressure baroreceptors (bare ends of myelinated nerve fibers) are located at strategic low-pressure sites including the (blank) and monitor venous volume.

Answer 18

pulmonary artery, the junction of the atria with their corresponding veins, the atria themselves

Question 19

(blank) receptors help control blood volume through reflex release of antidiuretic hormone.

Answer 19

Low pressure baroreceptors

Question 20

(blank) is a collection of neurons in the medulla of the brain that receives sensory information from a variety of sources, compares this information with the set point for systemic arterial blood pressure, and initiates responses to maintain an appropriate blood pressure.

Answer 20

Cardiovascular center

Question 21

The CV center also receives information from higher areas in the brain such as hypothalamus, limbic system, and cerebral cortex. Input from these areas can override the (blank)

Answer 21

homeostatic activity of the cardiovascular system.

Question 22

What are the effector organs of ANS cardiovasculor system?

Answer 22

heart and blood vessels

Question 23

An increase in blood pressure is translated into an increase in (blank). This in turn inhibits (blank) from the CNS. The opposite is also true.
Is this response immediate or slow?

Answer 23

baroreceptor nerve firing
efferent sympathetic nerve activity
immediate

Question 24

Acute hemorrage will do what do you mean arterial pressure?

Answer 24

decrease it

Question 25

A decrease in mean arterial pressure will (blank) stretch on carotid sinus barocreceptors?

Answer 25

decrease

Question 26

A decrease in stretch on carotid sinus baroreceptors will (blank) firing rate of carotid sinus nerve (hering's nerve)

Answer 26

decrease

Question 27

A decrease in firing rate of carotid sinus nerve leads to what 2 things?

Answer 27

decrease parasympathetic outflow to the heart and Increase sympathetic outflow to heart and blood vessels

Question 28

A decresae in parasympathetic outflow to the heart will do what to heart rate?

Answer 28

increase heart rate

Question 29

If you increase sympathetic outflow to heart and blood vessles what will happen to heart rate and contractility, arterioles?

Answer 29

increase in both, and constriction of arterioles

Question 30

If you have an increase in constriction of blood vessels, increase in mean systemic pressure, increase of venous return what will happen to your mean arterial pressure?

Answer 30

it will increase

Question 31

What happens if you increase aortic pressure?

Answer 31

Increased aortic pressure leads to increased afferent nerve activity from the baroreceptors, which results in reciprocal changes in efferent sympathetic and parasympathetic nerve activity to the heart and blood vessels with a resultant decrease in aortic blood pressure back to normal.

Question 32

What happens if you have acute hemmorage?

Answer 32

barorecptors sense decreased stretch which tells sympathetic NS to incresae which will cause vasoconstriction which will increase blood pressure towards normal

Question 33

What happens if you elevate arterial pressure?

Answer 33

you will increase barorecptor stretch which will increase parasympathetic activity which will decrease resistance, decrease stroke volume and cardiac output to attempt to return arterial presure back to normal

Question 34

Massage of the neck over the carotid sinus area in a person experiencing a bout of paroxysmal atrial tachicardia is often effective in terminating the episode. Why?

Answer 34

trick brain into thinking you have increase receptor activity of baroreceptors

Question 35

What would happen to blood pressure if the arterial baroreceptors were surgically cut?

Answer 35

you will have an increased range of blood pressure

Question 36

What would happen to blood pressure if BOTH the arterial and cardiopulmonary baroreceptors were surgically cut?

Answer 36

The arterial pressure would shift to the right and be much higher. Large fluctuations in BP

Question 37

Baroreceptors are the primary sensors for (blank) blood pressure control.

Answer 37

acute

Question 38

A second set of receptors, the peripheral (blank) , also play a role in BP.

Answer 38

chemoreceptors

Question 39

The purpose of the Arterial Chemoreceptors is to buffer ACUTE changes in (blank)

Answer 39

pO2 , pCO2 , and pH

Question 40

What do the arterial chemoreceptors sense?

Answer 40

hypoxemia, hypercapnia, and acidosis (typically during ischemia and hemorrage)

Question 41

(blank) have high rates of O2 consumption and are, therefore, sensitive to decreases in the partial pressure of O2 (PO2).

Answer 41

peripheral chemoreceptors

Question 42

In (blank) decreases in PO2 activate vasomotor center that produce vasoconstriction, increase in TPR, and increase in arterial pressure.

Answer 42

peripheral chemoreceptors

Question 43

If you have reduced oxygen, what will happen in the peripheral chemoreceptors?

Answer 43

Increase in Total peripheral resistance and increase in arterial pressure

Question 44

Decreases of pO2 less than 60 mm Hg cause (blank)

Answer 44

hyperventiliation

Question 45

For the cardiovascular system, the peripheral chemoreceptors play a role only during (blank)

Answer 45

severe hypoxia (e.g., hemorrhagic hypotension).

Question 46

The (blank) is not a powerful arterial pressure controller in the normal BP range (they are stimulated when the pressure falls below 80 mm Hg).

Answer 46

peripheral chemoreceptor reflex

Question 47

What do central chemoreceptors in the medulla do and what do they respond to?

Answer 47

Control breathing. Increases in pCO2 and [H+] stimulate breathing, and decreases in pCO2 and [H+] inhibit breathing. The resulting hyperventilation or hypoventilation then returns the arterial PCO2 toward normal. Responds to CO2 and H+

Question 48

The net effect of stimulation of both peripheral and central chemoreceptors is (blank) , and increased TPR (and blood pressure).

Answer 48

tachicardia

Question 49

The renin-angiotensin-aldosterone system plays an important role in the regulation of (blank) .

Answer 49

arterial blood pressure and blood volume

Question 50

RAAS is triggered by a (blank) in renal perfusion pressure.

Answer 50

decrease

Question 51

RAAS is a relatively slow, hormonal mechanism and is used in (blank) by adjustment of blood volume and vascular resistance.

Answer 51

long-term blood pressure regulation

Question 52

(blank) is released in response to hemorrhage (decreased blood volume)

Answer 52

vasopression (ADH)

Question 53

(blank) is released in response to activated low-pressuer baroreceptors

Answer 53

vasopression (ADH)

Question 54

(blank) causes vasoconstriction (mediated by V1 receptors) (blank) increases water reabsorption (mediated by V2 receptors) and ultimately increases blood volume and interstitial fluid volume.

Answer 54

vasopressin (ADH)

Question 55

The amount of extracellular fluid effects (blank)

Answer 55

blood pressure

Question 56

increased extracellular fluid volume increases the (blank) . Note especially that increased cardiac output has both a direct effect by increasing arterial pressure and an indirect effect by increasing the total peripheral resistance.

Answer 56

arterial pressure

Question 57

What is released from the atria in response to increase atrial pressure?

Answer 57

ANP,BNP (natriuretic peptides)

Question 58

What causes vasorelaxation and decreased total peripheral resistance?

Answer 58

ANP,BNP (natriuretic peptides)

Question 59

(blank) cause increased excretion of Na+ and water by the kidney (reduces blood volume).

Answer 59

ANP,BNP (natriuretic peptides)

Question 60

(blank) inhibits renin secretion.

Answer 60

ANP,BNP (natriuretic peptides)

Question 61

When you have CNS ischemic response what happens?

Answer 61

increased sympathetic and parasympathetic response but Parasympathetic is more substantial which will decrease the heart rate

Question 62

During a disturbance in arterial pressure, what is first to respond?

Answer 62

baroreceptors (powerful) then chemoreceptores (not as powerful)

Question 63

During a disturbance in arterial pressure, when do you have ischemic brain reflexes?

Answer 63

after chemoreceptors react

Question 64

What is last to respond during a distrubance of arterial pressure?

Answer 64

renal mediated fluid retention and aldosterone

Question 65

Each of the various factors operates over its own particular range of arterial pressure. For example, the is a very powerful reflex that is the last-ditch effort of the body to preserve cerebral circulation. It operates only when the arterial pressure falls to a very low level. In contrast, the baroreceptors operate over a range of pressures that one would encounter in everyday life.

Answer 65

CNS ischemic response

Question 66

What are the high pressure baroreceptors? | Low pressure?

Answer 66

aortic/carotid | Cardio/pulmonary

Question 67

What do peripheral chemoreceptors do?

Answer 67

vasconstrict , decrease HR

Question 68

What do central chemoreceptors do?

Answer 68

increase breathing, Increased HR

Question 69

What is the net effect if both kinds of chemoreceptors are stimulated?

Answer 69

tachycardia, and increased BP