Special Circulations: Cerebral, Skeletal, Splanchnic, Cutaneous

Question 1

What does autoregulation in cerebral blood flow do?

Answer 1

Ensures that changes in arterial pressure do not dramatically affect CBF

Question 2

What causes Cushing reflex?

Answer 2

Reduced CBF; used to maintain flow

Question 3

What do sensory nerves that run with cerebral arteries contain?

Answer 3

Substance P and calcitonin gene related peptide

Question 4

What do substance P and CGRP cause?

Answer 4

Vasodilation

Question 5

What do cerebral veins converge into?

Answer 5

Pial plexus

Question 6

What prevents solutes in blood from accessing brain ECF?

Answer 6

Blood brain barrier

Question 7

Local production of what cause vasodilation?

Answer 7

Adenosine, CO2, decreasing pH

Question 8

What are the primary stimulus for vasodilation in SM?

Answer 8

Adenosine, CO2, K+

Question 9

What is hyperemia?

Answer 9

Excess blood vessels supplying an organ

Question 10

At rest what controls splanchnic circulation?

Answer 10

Autonomics

Question 11

After a meal what controls splanchnic circulation?

Answer 11

CNS

Question 12

What does the enteric nervous system control?

Answer 12

Peristalsis of the intestine; receives sensory info and sends motor from CNS

Question 13

What does right sided heart failure cause?

Answer 13

Increased CVP and increased filtration by the liver leading to ascites

Question 14

When do sympathetics cause control cutaneous blood flow?

Answer 14

In regulation of body core temperature

Question 15

What is cutaneous flow divided into?

Answer 15

Apical

Nonapical

Question 16

What are glomus bodies?

Answer 16

Arterial-venous anastomoses found in apical skin only

Question 17

What controls glomus bodies?

Answer 17

Neural control; norepi

Question 18

What is the function of glomus bodies?

Answer 18

Vasoconstricts in response to cold skin sensors or cold core temperature to conserve heat

Question 19

Where is apical skin flow found?

Answer 19

Nose, lips, ears, hands and feet

Question 20

What controls non-apical skin blood flow?

Answer 20

Norepi and acetylcholine

Question 21

What is the effect of sympathetics on non-apical skin?

Answer 21

Ach to vasodilate

Question 22

What is the triple response of cutaneous flow and what causes each?

Answer 22

Red reaction: increased cap perfusion from histamine
Flare reaction: spread of redness, dilation of arterioles by axon reflex
Wheal: edema from cap permeability