Inflammation Flashcards
What is stress?
a state manifested by a specific syndrome of the body developed in response to any stimuli that made an intense systemic demand on it
What parts of the nervous system play a role in the stress response?
Neuronal pathways, RAS, cerebral cortex, limbic system, thalamus, hypothalamus, pituitary gland
What are the residual effects that may occur following a stress response?
-Headaches, nausea, insomnia, and emotional disturbances
-Prolonged or frequent stress responses can lead to: Ulcers, CV and kidney disease, long term mental health issues, reproductive issues, irregular menstruation, under/overactive stress response
What does Corticotropin-Releasing Factor (CRF) do?
-Secreted by the hypothalamus
-Induces secretion of Adrenocorticotropic Hormone (ACTH) from the anterior pituitary gland
What does Adrenocorticotropic Hormone (ACTH) do?
-Secreted by the anterior pituitary gland
-Stimulates the secretion of cortisol (glucocorticoid hormone) from the adrenal glands
What does cortisol do?
-Secreted by the adrenal glands
-Maintains blood glucose levels, enhances effects of CV catecholamines, inhibits less essential activities (hematopoiesis, immune responses, etc
What does Angiotensin II do?
-Stimulates release of norepinephrine, enhances CRF formation and release, causes vasoconstriction
-Key part of the Renin-Angiotensin-Aldosterone system
What does Antidiuretic Hormone (ADH) aka vasopressin do?
-Secreted by the posterior pituitary gland
-Increased water retention by the kidneys, vasoconstriction
-Many other hormones are involved in smaller roles, and many are not fully understood
What is suppressed during stress response?
The bodies stress response also suppresses its immune response
What are red blood cells (aka erythrocytes)?
-Most abundant formed element
-Primary function is transport of O2 and CO2 via hemoglobin
What is hemoglobin
-Globin protein and 4 heme rings
-Each heme ring contains iron ion (Fe2+) that binds to one O2 molecule - each hemoglobin molecule binds with 4 O2
What is erythropoiesis?
The production of RBCs in the red bone marrow
What are white blood cells (aka leukocytes)?
-Granular or agranular, based on having cytoplasmic granules
-Short lifespan (even shorter during inflammation /infection)
What are neutrophils?
phagocytes (most abundant WBC)
What are eosinophils?
combats histamine in allergic reactions
What are basophils?
intensifies inflammatory response in allergic reactions
What are lymphocytes?
immune response (B cells, T cells)
What are monocytes?
phagocytes (become macrophages when the migrate)
What is leukocytosis?
increased circulating WBCs (normal during infection, inflammation, stress, etc)
What is leukopenia?
decreased circulating WBCs (not normal)
What are platelets?
-Membrane enclosed fragments of larger cells
-Lifespan of 5-9 days
-Contain and release chemicals to promote blood clotting
-Aggregate (stick together) to form a platelet plug
What is hemostasis?
sequence of events to stop bleeding
What is inflammation?
-The reaction of vascularized tissues to an injury
-Involves a wide variety of physiologic and pathologic responses intended to eliminate the initial cause of cell injury, removal of damaged tissue, and generation of new tissue
What is added to a word for inflammatory conditions?
The suffix -itis is typically added
What are the signs and symptoms of inflammation?
(PRISH)
Pain - release of certain chemicals
Redness - increased blood flow to affected area
Immobility - loss of function
Swelling - accumulation of fluids
Heat - increased blood flow to affected area
What is acute inflammation?
-The early protective response of local tissues and their blood vessels to injury
-Relatively short duration (minutes to days)
-Critical to the restoration of homeostasis
-Occurs before adaptive immunity is established and is aimed at removing the injurious agent and limiting the extent at tissue damage
What can acute inflammation be triggered by?
Infections, immune reactions, blunt and penetrating trauma, physical or chemical agents, tissue necrosis
What are the 2 components of acute inflammation?
Vascular stage (increased blood flow) and cellular stage (migration of leukocytes)
What cells and tissues are involved in this process?
Endothelial, WBCs, connective tissue cells (mast cells, fibroblasts, macrophages, lymphocytes), extracellular matrix (ECM)
What is the ECM?
fibrous proteins (collagen and elastin), adhesive glycoproteins, proteoglycans
What are endothelial cells?
Single-cell inner lining of blood vessels
What do endothelial cells do in acute inflammation?
-produce antiplatelet and antithrombotic agents that maintain vessel patency and vasodilators and constrictors that regulate blood flow
-function as a selectively permeable barrier to inflammatory stimuli
-regulates leukocyte extravasation
-movement of leukocytes out of circulation toward damaged tissue
-synthesizes and releases inflammatory mediators
What do platelets do in acute inflammation?
-Once activated, they release inflammatory mediators to aid in the process
-Over 300 proteins are released
-Causing increased vascular permeability and altered endothelial adhesion
What do neutrophils do in acute inflammation?
-Primary phagocyte that arrives to the inflammatory site early
-Granules contain enzymes and antibiotic material that are used to destroy engulfed microbes or dead tissue
-Neutrophil count in the blood increases substantially during the inflammatory process
-After being released from the bone marrow they only have a lifespan of 10 hours - during inflammation, more are constantly being created and released (sometimes before they are fully mature)
What do monocytes and macrophages do in inflammation?
-Arrive at the inflammation site shortly after neutrophils and live longer
-Produce potent vasoactive inflammatory mediators to help promote the regeneration of tissues
-Play a key role in chronic inflammation
What do eosinophils, basophils, and mast cells do for inflammation?
-Produce lipid mediators and cytokines that induce inflammation
-Particularly important in immediate hypersensitivity reactions and allergic disorders