3C-Regulate Arterial BP!

Question 1

What is the relationship between CO, MAP, and TPR?

Answer 1

CO=MAP/TPR….or…..MAP=CO x TPR

Question 2

Which pathways generally control Short Term regulation of MAP? What are the targets of these pathways?

Answer 2

Neural pathways!…The heart and Blood Vessels

Question 3

Which pathways generally control long term MAP regulation? What are the targets of this system?

Answer 3

Endocrine pathways!…The kidneys and blood vessels

Question 4

What are the Short term regulators? What two places are they located?

Answer 4

Baroreceptors! Carotid Sinus & Aortic Arch

Question 5

Which CN’s carry signals from baroreceptors?

Answer 5

IX glossopharyngeal & X Vagus (ahhh it feels good to say those again!)

Question 6

Where do the CN’s deliver the message from the baroreceptors?

Answer 6

The brainstem—MEDULLARY CARDIOVASCULAR CENTER

Question 7

What type of response does the medullary cardiovascular center employ to control hyper and hypotension?

Answer 7

SymNS and ParasymNS

Question 8

What are the three steps taken by the medullary cardiovascular center to in response to LOW BP?(opposite steps for response to high BP)

Answer 8

1.Increase SymNS cardiac nerve activity 2.Increase SymNS vasoconstrictor nerve activity 3. Decrease ParasymNS

Question 9

What happens after all of the neruo response to LOW BP? What are the four things affected? That increase BP back to normal? (opposite response to high BP)

Answer 9

VasoConstricion therefore Increased HR and SV which increases CO and TPR

Question 10

What is it called when an old person gets up too fast and their baroreceptor reflex is too slow to compensate?

Answer 10

Orthostatic Hypotension

Question 11

After a gunshot wound/acute hemmorage, what can increase the amount of blood sent back to the heart? What hormone probably causes this?

Answer 11

Constriction of veins increases amount of blood back to the heart! ADH! Hypovolemia is a potent stimulus for ADH secretion!

Question 12

What can frequently alter the sensitivity of baroreceptors?

Answer 12

DISEASE!

Question 13

What is the LONG term pathway for regulating blood pressure??

Answer 13

RAA Pathway (Renin, Angiotensin, Aldosterone)

Question 14

What do the kidneys secrete in response to decrease in blood pressure?

Answer 14

Renin!!

Question 15

What does Renin catalyze?

Answer 15

The conversion of Angiotensinogen to Angiotensin I in the plasma

Question 16

What converts Angiotensin I to Angiotensin II?

Answer 16

Angiotensin Converting Enzyme (ACE)

Question 17

What are the 4 effects of Angiotensin II?

Answer 17

1.Secrete ALDOSTERONE from adrenal cortex(salt/water retention) 2.DIRECTLY on the kidney for water/salt retention 3.VERY potent VASOCONSTRICOR 4.Brain for ADH release and THIRST

Question 18

Where is Vasopressin/ADH secreted?

Answer 18

Posterior Pituitary

Question 19

What is the MOST IMPORTANT physiologic stimulus for increasing ADH secretion?

Answer 19

Increased plasma osmolarity ( increased solute concentration in blood)…EAT SALT IN MOVIE THEATRE!

Question 20

What are the two modes of action for vasopressin/ADH to increase BP back to normal? What receptors are involved?

Answer 20

1. Increases Water reabsorption in the KIDNEYS VIA V2 Receptors 2. Potent Vasoconstriction VIA V1 receptors on the arterioles

Question 21

What hormone is used to LOWER blood volume and therefore Blood Pressure?

Answer 21

ANP! Anti Natri-uretic Peptide

Question 22

Where is ANP secreted and how does it work (2 ways)?

Answer 22

AntiNatriuretic Peptide is secreted by the ATRIA of the heart….. causes 1. EXCRETION of Sodium and Water 2.VasoDilation

Question 23

What are the two hormonal regulations for increased BP?

Answer 23

1. Increase ANP 2.Decrease ADH

Question 24

What 2 things work together to promote venous blood flow in the legs and to prevent vericose veins?

Answer 24

1.The Skeletal Muscle Pump 2.Venous Valves