Regulation Of Arterial Pressure

Question 1

What N. Correspond to the Carotid sinus baroreceptor

Answer 1

Glossopharyngeal N. (CN IX)

Sinus N of Hering

Question 2

What N.’s correspond to the Ao. Sinus Baroreceptor

Answer 2

Vagus N. (CN X)

Aortic N.

Question 3

The afferent pathways of the baroreceptor reflex go to where in the brain and what neruoxmitter do they use here

Answer 3

The nucleus tractus solitarius (NTS)

glutamate as neuroxmitter

Question 4

What do baroreceptors sense

Answer 4

Change sin pressure through stretch receptors on vessel walls

Question 5

Increased stretch (increased MAP) will cause what in the baroreceptors

What about decreased stretch

Answer 5

Increased firing of parasympathetic N.S. (Need to chill out with amount of blood)

Decreased firing of parasympathetic N.S with pressure and stretch decrease, and sympathetic N.S takes over

Question 6

The baroreceptors are most responsive to what

Answer 6

The rate of change in pressure

Question 7

Increased stretch and thus increased pressure causes what in terms of paraympathetic and sympathetic N.S.

Answer 7

Increased stretch means increased MAP and thus increased paraympathetic N.S. And decreased sympathetic N.S.

Question 8

The parasympathetic efferent response travels through what in the brain

Answer 8

The dorsal motor nucleus of the vagus and the nucleus ambiguus

Question 9

The sympathetic efferent signal travels through what in the brain

Answer 9

Rostral ventrolateral medulla

Question 10

SV is dependent on what

Answer 10

Sympathetic stimulation

Preload

Question 11

HR is dependent on what

Answer 11

Symp and Parasymp Stimulation

Question 12

Increased frequency of stimulation does what in terms of parasympathetic firing and what does this mean physiologically

Answer 12

Increases strength of AP

Fires until about 200 mmHg, then levels out

Question 13

The aortic sinus has a what compared to the carotid sinus and is less sensitive to what

Answer 13

Higher threshold for activation and less sensitive to rate or decrease in AP

Question 14

What receptor increases Hr and contractility

What about constriction of arterioles and veins

Answer 14

B1

A

Question 15

What N effects the SA node paraympathetically and with what receptor

Answer 15

Vagus N to SA Node with mAChr

Question 16

How does HTN effect baroreceptors

Answer 16

Resets them to a higher set point

Question 17

What does the RAAS control in general terms

Answer 17

Long-term regulation of blood volume

Question 18

Renin is stimulated by what receptors

Answer 18

B1

Question 19

Renin is secreted from what

Answer 19

Juxtaglomerular (JG) cells in the kidneys in response to low BP and sympathetic stim.

Question 20

What does Angiotensin II bind to in arterioles to cause vasoconstriction and what does this mean physiologically

Answer 20

AT1 receptors which increases TPR and BP

Question 21

What receptors does vasopressin act on

Answer 21

V1 (SM) and V2(collecting ducts) to increase TPR and water retention

Question 22

What does ANPs do and when is it secreted

Answer 22

Secreted during excessive preload of atria and vent.

Causes arteriolar dilation - decreased TRP

Increased fluid loss - decreases preload

Inhibits renin

Question 23

A decrease in VR, preload, SV, Co and MAP will do what to the vascular function curve

Answer 23

Shift it L (decreased pressure in LV)

Question 24

What receptors in the atria sense changes in blood volume

What about the ventricles

Answer 24

A fibers

B fibers

Question 25

What receptor is acted on during exercise and what happens physiologically

Answer 25

B1

Increased symp., decreased parasymp.

Increased HR/inotropy

Increased VR

Slight increase in MAP

Question 26

Vasopressin is secreted in response to what and what does it do

Answer 26

ANG II, low preload

Increases TPR and water retention