acute inflammation (W11)

Question 1

tissue requirements for inflammation

Answer 1

living, vascularised

Question 2

inflammation functions

Answer 2

remove cause (if possible)
prevent infection
engage process of repair

Question 3

what is the name for the fluid, proteins and cells which leave the circulation and go into the interstitial space in inflammation

Answer 3

inflammatory exudate

Question 4

examples of danger signals that small blood vessels and the extracellular matrix respond to?

Answer 4

damaged matrix
stressed/dying tissue cells
mast cells
pathogens

Question 5

what do mast cells produce?

Answer 5

histamine

Question 6

what sustains inflammation in substantive injury

Answer 6

cytokines

Question 7

what is a major factor in burns? important treatment?

Answer 7

large surface area inflamed therefore lots of exudate being delivered. important to start rapid fluid replacement quickly.

Question 8

what type of process is exudate leak and tissue swelling? why can this be a problem?

Answer 8

active process, therefore if there is sufficient signalling for inflammation, fluid will continue to be delivered from the circulation and this can occur until your heart fails as circulation no longer supported

Question 9

when does passive leaking occur -example

Answer 9

sunburn (endothelial cell damage, apoptosis, spaces in blood vessels)

Question 10

where are white blood cells present when circulating

Answer 10

pushed towards walls due to haemodynamics of normal blood flow

Question 11

what occurs in the circulation when fluid is lost in exudate

Answer 11

red blood cells clump together into rouleux physically pushing white blood cells to the edge

Question 12

what stops inflammatory cells from sticking to healthy endothelium

Answer 12

glycocalyx ‘lawn’

Question 13

what breaks down locally in response to danger signals and why

Answer 13

glycocalyx - allows cells (neutrophils in acute inflammation) to touch endothelium and adhesion molecules

Question 14

what danger signals cause endothelium to shed glycocalyx

Answer 14

DAMP and cytokines (TNF, IL-1)

Question 15

platelets role in neutrophils exiting tissue?

Answer 15

bind to and boost endothelial activation

Question 16

where do white blood cells leave in nearly all tissues

Answer 16

venuoles

Question 17

where do white blood cells leave in nearly all tissues? exception?

Answer 17

venules
lungs are an exception

Question 18

what do neutrophils use to travel

Answer 18

matrix - fibrin scaffold

Question 19

why are swollen tissues that aren’t inflammatory immunocompromised?

Answer 19

gaps between connective tissue and no fibrin scaffold for neutrophils to crawl over

Question 20

what covers up small damage from neutrophils and why

Answer 20

resident macrophages in tissue will cover up small damage as don’t want area to become inflamed - eg minor skeletal muscle damage after physical exercise

Question 21

what does the lead neutrophil in inflammation do if the level of danger is high enough?

Answer 21

lead neutrophil will explode and leave a pool of high inflammatory material that activates further neutrophils

Question 22

what do neutrophils leave behind them after they exit the blood vessels? why?

Answer 22

trail of granule proteins that monocytes can sense and follow

Question 23

what do monocytes mature to

Answer 23

macrophages

Question 24

types of exudate?

Answer 24

pus (neutrophil, enzymes, yellow/green)
fibrinous (fibrin>cells, greyish)
serous (fluid>cells)
haemorrhagic (vascular destruction)

Question 25

what occurs to lymphatics in inflammation

Answer 25

tissue swelling causes vessels to open up, capacity to allow fluid through increases

Question 26

what additionally passes through lymphatics in inflammation

Answer 26

exudate (so contents can be sampled in lymph nodes)

Question 27

pain and inflammation?

Answer 27

not all inflammation is painful - eg no pain sensation inside lung (but if pleura is inflamed then pain related to breathing occurs)