26: Unique regional circulations

Question 1

Characteristics unique to different vascular beds

Answer 1

1. Balance of intrinsic vs extrinsic
2. A-1 or 2 or B2 receptor concentration
3. Unique anatomical structure

Question 2

Extrinsic

Answer 2

autonomic nervous system

Hormonal regulation through receptors

Question 3

Intrinsic

Answer 3

Autoregulation to environment

Automatic response of cells to metabolies

Question 4

Cutaneous circulation

Answer 4

extrinsic control mechanisms predominate
High A-receptor concentration
low metabolic demands of skin

Question 5

What sets temperature

Answer 5

Hypothalamus

Question 6

Features of skin

Answer 6

Large
arterio-venous shunts to divert blood
Metabolic escape

Question 7

Skeletal bed

Answer 7

Large vascular bed

Both extrinsic and intrinsic regulation

Question 8

What happens during activation of skeletal muscle

Answer 8

Intrinsic regulation overrides sympathetic activation

Question 9

what receptor causes muscle vasculature vasodilation

Answer 9

b-2 receptors

Question 10

What happens during exercise

Answer 10

adrenal stimulation
epinephrine release
Intrinsic control must quickly meet metabolic needs

Question 11

What is an important regulator of muscle venous return

Answer 11

muscles pumping as they move

Question 12

How does skin a muscle vaculature respond to sympathetic drive

Answer 12

Very sensitive

Smooth muscle constricts to increase resistance

Question 13

Coronary circulation

Answer 13

Intrinsic mechanisms dominate

low A receptor conc

Question 14

Vasodilators of coronary circulation

Answer 14

Increase: CO2
Decrease: O2, H+, and adenosine

Question 15

Cerebral circulation

Answer 15

Metabolic regulation predominates

Tightly regulated

Question 16

main controller of metabolic regulation

Answer 16

CO2

Question 17

Splanchnic circulation

Answer 17

Sympathetic innervation important: shunts blood away from non vital

Question 18

Liver

Answer 18

Portal vein does not autoregulate during prolonged constriction

Question 19

Ascites

Answer 19

increased peritoneal cavity fluid

Right heart failure

Question 20

Ascites- hepatic hypertension

Answer 20

hepatic portal venous pressure rises

Hepatic scarring- increased resistance to inflow

Question 21

Pulmonary circulation

Answer 21

Low resistance

Respond to increase in perfusion pressure with a decrease in resistance

Question 22

In pulmonary circulation, what does hypoxia trigger

Answer 22

vasoconstriction

Question 23

What is a cause of pulmonary hypertension

Answer 23

high altitude