Inflammation Flashcards
What is a vital reaction
Only happens in living tissue
Ex: Inflammation
5 cardinal signs of inflammation
- Calor (heat)
- Rubor (redness)
- Tumor (swelling)
- Dolor (pain)
- Functio laesa (disturbed function)
4 major categories of changes in inflammation
Circulatory
Vascular
Humoral
Cellular
Circulatory changes
First response to injury is change in blood flow
Increased blood flow to capillaries = redness, swelling, warmth
Inflammatory edema leaks from capillaries and venules due to increased pressure
Hyperemia definition
Increased blood flow
Rouleax
More than 4 red blood cells stacked together
Go to the middle of the flow and slow it
Due to proteins covering the negative charges so they can stick together
3 steps in pathogenesis of inflammation
- Margination of neutrophils
- Adhesion of platelets
- Pavementing of neutrophils
Vascular changes
Increased permeability (caused by 4 things)
4 things that cause increased permeability
Increased hydrostatic pressure
Slowed circulation
Leukocyte and platelet adhesion to endothelial cells
Soluble mediators
2 classes of inflammatory mediators and what defines them
- Plasma derived (need to be activated)
2. Cell-derived (pre-fromed, formed de novo, or may need to be activated)
Histamine
Releases from platelets and mast cells
Stimulates contraction of endothelial cells
Inactivated by histaminase, so is an immediate transient reaction
Enzyme that inactivates histamine
Histaminase
Bradykinin
Works like histamine but slower
Also causes pain
2 complement proteins that are anaphylatoxins
C3a
C5a
Arachadonic acid
Part of cell membranes
Has to be acted on by enzymes to do anything
2 paths that arachadonic acid can enter
- Lipoxygenase pathway
2. Cyclooxygenase pathway
Lipoxygenase pathway
Makes leukotrienes and lipoxins
Leukotrienes
Promote chemotaxis and increase vascular permeability
Cause contraction of smooth muscle (bronchospasm)
Allergy and anaphylaxis
Lipoxins
Negative regulators
Counteract the effects of leukotrienes
Cyclooxygenase pathway
Makes thromboxanes, prostaglandins, and prostacyclins
Thromboxanes
Promote platelet aggregation and vasoconstriction
Prostaglandins
Cause vasodilation and increased permeability
Pain and fever
Prostacyclin
Negative regulator
Counteracts effects of thromboxanes and prostaglandins
Transudation
Leakage of fluid into interstitial space
Transudate
Fluid that leaks out of leaky vessels at site of inflammation
Has lots of proteins and few blood cells
Exdate
Formed by emigration of cells across vascular walls
More protein that transudate
Contains inflammatory cells
Neutrophils
Also called polymorphonuclear cells Most abundant WBC Involved in acute inflammation Mobile, phagocytic, acute mediator, involved in pain Short life spane
Monocyte
Big phagocytic cell
Turns into macrophage in tissue