Chapter 16: Inflammation Flashcards
What is inflammation?
Bodys defensive response to tissue damage from microbial infection. It is also a response to mechanical injury, heat, electricity, UV lights, Chemicals and allergies
Cardinal signs and symptoms of inflammation
(1) Calor: increase in temp
(2) Rubor: Redness
(3) Tumor: Swelling
(4) Dolor: Pain at the infected or injured site
Acute inflammation
(1) Battle between host and antigen where host ultimately wins (2) Kill invading microbes, Clear away tissue debris, Repair injured tissue
Histamine
Chemical substance released from basophils and mast cells
Where do histamines diffuse?
Capillaries and venules which lead to vasodilation
What is an edema due to histamine release?
When blood accumulates to infected site and causes swelling
What re blood clotting factors?
Fibrin
What is the purpose of blood clotting?
Reduces fluid movement around damaged cells and walls off the injured area from the rest of the body
What is pain due to?
(1) Released from Mast cells (2) Pain is associated with tissue injury and the release of bradykinin which is a small peptide causing blood vessels to dilate (3) Mediates inflammation (4) Prostaglandins intensify bradykinin
Inflamed tissue stimulates leukocytes, what are Leukocytes?
(1) An increased number of leukocytes in the blood (2) They work because damaged cells release cytokines that trigger production and infiltration of leukocytes
How do neutrophils pass out of the blood?
Through squeezing between endothelial cells lining the vessel walls
Diapedesis
Process that allows for neutrophils to congregate in the tissue fluid at the injured region
Histamines attract which cells to the injury site?
(1) Leukocytes (2) Bradykinin (3) Neutrophils (4) Macrophages which release cytokines and chemokines sometimes
Antihistamine
Alleviates symptoms caused by histamines by blocking the released histamine from reaching its receptor on target organs
When microbes produce more leukocidins to destroy phagocytes what is produced?
Pus
Can viruses produce pus?
No
Abscess
An accumulation of pus in a hallowed out cavity due to tissue damage (boils and pimples)
Repair and Regeneration
(1) Capillaries grow into blood clots and fibroblasts (2) Connective tissue cells replace the destroyed tissue
Granulation tissue
Fragile, red tissue at the injury site consisting of capillaries and fibroblasts
What happens after granulation tissue is formed?
Fibroblasts and fibers replace nerve and muscle tissue that cannot be regenerates and new epidermis goes on top
Chronic inflammation
Inflammation of the host where neither the antigen or the host can win the battle
Granulomatous inflammation
Results in granulomas which are pockets of tissue that surround and walls off the inflammatory agent to suppress chronic inflammation
Granuloma
Epithelial cells and macrophages
What do pyrogens cause?
Fever
Inflammatory response: (Steps 1-4)
(1) Cut allows bacteria to enter body (2) Damaged cells release histamine and bradykinin (3) Capillaries dilate to bring in more blood to the tissue, skin heats up and turns red (4) Capillaries dilate and edema occurs
Inflammatory response (Steps 5-9 after edema forms)
(5) Blood clot and scab forms (6) Bacteria multiply in cut (7) phagocytes enter tissue by moving through blood vessels “diapedesis” (8) Phagocytic cells are attracted to bacteria and tissue debris “chemotaxis” and engulf the antigens (9) Larger blood vessels dilate increasing blood supply to tissue adding heat and redness
Inflammatory response (10-11 repair process)
(10) Dead cells removed and epithelial cells proliferate and begin to grow under scab (11) Scar tissue “connective tissue” replaces cells that cannot replace themselves
