Flashcards in Chapter 3 - Inflammation and Repair Deck (118)
Define acute inflammation.
AI: transient and early response to injury
What three responses are involved in acute inflammation?
AI: chemical, vascular, cellular responses
Rubor, calor, and dolor are mediated by what?
Rubor, calor, tumor: histamine-mediated
Dolor is mediated by what two compounds?
Dolor (pain): mediated by PGE2 and bradykinin
What mediates vasodilation of arterioles?
Vasodilation of arterioles: histamine, nitric oxide
In acute inflammation, what do mast cells release?
Mast cells: release preformed histamine
How does histamine affect venule endothelial cells resulting in what?
Histamine: contracts venule endothelial cells; ↑venular permeability
Describe edema fluid.
Edema fluid: transudate (low protein and cell levels)
What are the primary leukocytes in acute inflammation?
Neutrophils: primary leukocytes in AI
How does the circulating pool and marginating pool of neutrophils differ between Caucasians and African Americans?
Neutrophils: in white people, 50% circulating and 50% marginating; in black people, marginating pool > circulating pool
What alters the distribution of neutrophils?
Neutrophil distribution: altered by activating/inactivating adhesion molecules
What does margination of neutrophils mean?
Margination: neutrophils pushed to periphery
What are selectins?
Selectins: carbohydrate-binding adhesion molecules
Where are L-selectin ligands located?
L-selectin: selectin ligand on leukocytes
Where are E-selectin molecules located?
E-selectin: selectin molecule on endothelial cells
From where is P-selectin derived?
P-selectin: derived from Weibel-Palade bodies in endothelial cells
What two cytokines activate selectins?
Selectins activated by IL-1 and TNF
Describe the process of selectin adhesion.
Selectin adhesion: “rolling” (bind−detach) of neutrophils
What do β2-Integrins do and what are they activated by?
β2-Integrins: firm adhesion of neutrophils; activated by C5a/LTB4
How catecholamines and corticosteroids affect the firm adhesion of neutrophils?
Catecholamines and corticosteroids inactivate neutrophil β2-integrins: produces neutrophilic leukocytosis
How do endotoxins affect β2-integrins producing what?
Endotoxins activate neutrophil β2-integrins: produces neutropenia
What are ICAM/VCAM and what are they activated by?
ICAM/VCAM: endothelial cell integrin adhesion molecules (ligands); activated by IL-1/TNF
Name one clinical finding of leukocyte adhesion deficiency due to selectin or CD11a/CD18 deficiency.
Delayed separation of umbilical cord: LAD due to selectin or CD11a/CD18 deficiency
Describe transmigration (diapedesis).
Transmigration (diapedesis): movement of neutrophils from venules into interstitial space
What is an exudate?
Exudate: protein- and cell-rich fluid (pus)
Name two functions of exudate.
Exudate: dilutes bacterial toxins; provides opsonins
What is chemotaxis?
Chemotaxis: directed migration of neutrophils
Name four chemotaxis mediators.
Chemotaxis mediators: C5a, LTB4, bacterial products, IL-8
Name two opsonins. What do they do?
Opsonins: IgG and C3b; enhance neutrophil ability to ingest bacteria
Opsonins: IgG and C3b; enhance neutrophil recognition and attachment of bacteria