microcirculation

Question 1

Why does reperfusion inactivate NO? When does this classically occur?

Answer 1

Reperfusion after an ischemia event leads to a generation of ROS which can inactivate NO and promote microvascular injury via increased luekocyte adherence/vascular permeability

Classically occurs during organ transplantation

Question 2

Net filtration

Answer 2

(Capillary pressure-Interstitial pressure) - (oncotic pressure of plasma proteins - (oncotic pressure of interstitial pressure)

Question 3

Under normal conditions interstitial pressure is about ____ and filtration is dependent on

Answer 3

zero, dependent on capillary pressure

Question 4

Liver disease can ___production of plasma proteins in the iver

Answer 4

impair

Question 5

kidney disease can ______ excretion of plasma proteins in urine

Answer 5

increase excretion

Question 6

Protein malnutrition is ______plasma protein production

Answer 6

impaired

Question 7

When plasma protein levels are reduced an plasma oncotic pressure is decreased, the force of reasborption of fluid into the capillaries is _____ which leads to an increase in interstitial fluid also known as

Answer 7

capillaries (reduced)

interstitial fluid increases (edema)

Question 8

where do lympathic vessles dump the excess ISF into?

Answer 8

Into the systemic circulation via the systemic veins

Question 9

how does edema impair exchange of metabolites between blood and tissue?

Answer 9

is increases the diffusion difference between capillaries and cells

Question 10

what are regulators of vascular smooth muscle activity

Answer 10

sympathetic vasoconstrictor nerves

hormones

local factors

endothelial-derived factors

change in vascular resistance

stretch of vessels

Question 11

which beta receptor promotes relaxation of vascular smooth muscle and is affected by epiephrine?

Answer 11

beta 2 (mainly on arterioles of skeletal muscle)

Question 12

When do Katp channels open?

Answer 12

when ATP levels are low

use of vasodilator drugs

Question 13

What is difference between an increase in Calcium in endothelial cells versus vascular smooth muscle?

Answer 13

Increase in calcium in endothelium= increase NO formation which dilates arterioles and increases blood flow

Increase in calcium in vascular smooth muscle= arteriolar constriction and decreased blood flow

Question 14

what amino acid is converted to Nitric Oxide?

Answer 14

Arginine

Question 15

4 main functions of NO

Answer 15

Vasodilator

Inhibits Leukocyte and platelet adherence

Maintains normal low vascular permeability

Antioxidant

Question 16

Endothelin-1 produced under _________ conditions, acts through membrane receptors on vascular ______ muscle and causes vasoconstriction by release of intracellular Calcium leading to an influx of calcium

Answer 16

produced under endothelial cell damage conditions (ischemia, reperfusion, hemorrhagic shock)

acts on vascular smooth muscle.