Intrinsic Regulation

Question 1

Blood flow to each tissue in the body

Functions of blood flow

Answer 1

Is almost always precisely controlled in relation to tissue need

Deliver blood, remove waste

Question 2

Rest vs exercise

Skeletal muscle/heart/skin
Brain
Abdomen

How does it occur?

Answer 2

Inc, Same, Dec

Increase in some tissues, dec to others
CO increases as well

Question 3

Blood flow equation

Answer 3

(Pi * Pressure change * r4)/(8nL)

Question 4

Blood flow is directly proportional to

Acute regulation is achieved by

Answer 4

4th power of radius- diameter has greatest role in determining BF

Adjusting tone of arteriole SM & radius of BV

Question 5

Acute blood flow control

Answer 5

Rapid changes in vasodilation/constriction of arterioles/metarterioles/precapillary sphincters w/in sec/min

Question 6

Tone of arteriole smooth muscle

Particular tone

Answer 6

Vascular smooth muscle, maintain a continuous level of constrictor tone

integrated effect of vasoconstrictor/dilator influences

Question 7

Acute blood flow regulation factors

Intrinsic (local)

Extrinsic (systemic)

Answer 7

I= actue/reactive hyperemia, autoegulation, flow dependent asodilation

E- neural, hormonal

Question 8

Active hyperemia

Direct result of

Answer 8

Inc blood flow when metabolic activity is inc

Arterioral dilation in active organ/tissue

Question 9

Local factors that cause arteriolar SM to relax

9 things

Answer 9

Dec O2
Inc CO2 (oxidative met)
dec pH
Adenosine
K+ ions (AP repolarize)
Eicosanoids (membrane phosphlipids)
Osmolarity (high MW)
Bradykinin
NO

Question 10

Reactive hyperemia

Clinical test

Answer 10

Response of tissue blood flow folling ischemia
- will increase

Ability of peripheral circulation to vasodilate

Question 11

Reactive hyperemia normal vs atherosclerotic following ischemia

Answer 11

N- rapid inc blood flow, overshoot

A- reduced, more gradual

Question 12

Autoregulation

Answer 12

Tendency of tissue BF to remain constant despite change in local perfusion pressure

Question 13

Posture and autoregulation

Head

Legs

Answer 13

1st- Arterial pressure to head dec, flow dec
2nd- returns to normal

`1- arterial pressure/flow inc
2- decrease to normal

Question 14

Mechanism of autoregulation

Myogenic

Metabolic

Degree of adjustment determined by

Answer 14

M- vascular SM contracts in response to inc pressure and relaxes w dec

Dec metabolites results in constriction

Collective effect

Question 15

Flow dependent vasodilation

Dependent on

Answer 15

Vessels dilate in response to inc flow

endothelium- release relaxing factors