EX 2; Regulation of Systemic Arterial Pressure

Question 1

This is the sum of the resistances to flow offered by all the systemic blood vessels

Answer 1

TPR; total peripheral resistance

Question 2

What is the equation for MAP

Answer 2

MAP = CO x TPR

Question 3

All changes in MAP must be the result of changes in what two things

Answer 3

cardiac output

TPR

Question 4

What is the equation for CO

Answer 4

CO = HR x SV

Question 5

Dynamic changes in vasodilation/vasoconstriction due to changes in the resistance of these can alter the MAP

Answer 5

arterioles

Question 6

This occurs to protect the maintenance of MAP

Answer 6

compensatory changes in arteriolar resistance

Question 7

What is the equation for flow

Answer 7

change in pressure/resistance

Question 8

Which portions of the body have their MAP regulated by local control

Answer 8

heart and brain

needed to control their own BP

Question 9

What portions of the body have their MAP regulated by neuronal control

Answer 9

GI
skeletal muscles
epithelium, etc.

Question 10

The sympathetic system acts upon which parts of the heart

Answer 10

atria and ventricles

Question 11

Sympathetic input to the SA node is via which receptors/channels

Answer 11

β receptor

funny channel

Question 12

Parasympathetic input uses this receptor/channel

Answer 12

muscarininc receptor

funny channel

Question 13

Sympathetic input to the vessels is via which receptor

Answer 13

α receptors

Question 14

How does the sympathetic system increase HR via the use of α and β channels

Answer 14

α on the vessels = vasoconstriction = increased TPR

β on ventricles = increased contractility and increased Ca = increased SV

Question 15

Blood loss causes a reduction in MAP, which is left unchecked would result in what

Answer 15

rapid and irreversible damage to the brain and the heart

Question 16

These function as sensors in the homeostatic maintenance of MAP by constantly monitoring pressure in the aortic arch and carotid sinus; *Main short term way to regulate MAP

Answer 16

baroreceptors

Question 17

The action potential frequency in baroreceptor neurons is represented here as being directly proportional to what

Answer 17

MAP

Question 18

Baroreceptor neurons deliver MAP information to where

Answer 18

the medulla oblongata’s cardiovascular control center; CVCC which determines autonomic output to the heart

Question 19

The information reported by baroreceptor neurons sets in motion autonomic responses to the heart (via CVCC) but also to where

Answer 19

arterioles and veins; this allows MAP to more readily be moved closer to the “set point”

Question 20

If arterial pressure decreases, the discharge rate of the baroreceptor does what

Answer 20

decreases

Question 21

What four things does a decrease in baroreceptor function induce

Answer 21

increased HR due to increased sympathetic activity and decreased parasympathetic activity
increased ventricular contractility (sym. activity)
arteriolar constriction (sym. activity)
increased venous contraction (sym. activity)

Question 22

The long term way to regulate blood pressure is through the use of what

Answer 22

an abnormal increase in MAP “squeezes” ,pre fluid out of the blood into the urine, leading to a reduction in blood volume, thus reducing MAP to the “set point”