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63 Cards in this Set
- Front
- Back
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What are the four general classes of lipids?
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triacylglycerol, phospholipid, steroid, glycolipid
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Steroids are derived from what molecule?
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cholesterol
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Where are bile salts and acids made and where are they stored?
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They are made in the liver and stored in the gallbladder.
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What is the function of bile salts and acids? What is the difference?
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Derivatives of cholesterol that aid in the emulsification of dietary lipids. Bile acids are not fully ionized.
Once a bile acid is conjugated by an amide bond and fully ionized, it becomes a bile salt. |
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What lipid molecule is the precursor for bile acid formation?
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Cholesterol
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What are the functional roles for CCK and secretin in lipid digestion?
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Cholecystoknin (CCK) triggers the gallbladder to release bile, activates the pancreas to secrete digestive enzymes and slows down the movement of gastric contents to the small intestine.
Secretin stimulates the liver and pancreas to release bicarbonate in order to neutralize intestinal contents and stabilize the pH for digestion. |
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What are the common causes of steatorrhea?
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When lipid digestion or absorption is disrupted, important fat-soluble vitamins can be excreted in feces.
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What is Celiac Disease?
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An autoimmune disorder in small intestine that can prevent the absorption of certain vitamins and minerals.
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Which vitamins are deficient in lipid malabsorption syndromes?
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A, D, E, K
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Which vitamin deficiency alters Prothrombin Time?
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Vitamin K helps with blood clotting so a deficiency can affect the amount of time it take for blood to clot (prothrombin time).
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Which vitamin alters Ca2+ and bone formation processes?
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Vitamin D increases the level of calcium uptake from the gut into the blood.
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What fats are in milk?
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Butyric and capric acid, fatty acids with 4-10 carbon chain lengths
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Name two common saturated fats in lipid membranes.
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palmitic acid and stearic acid
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Name two common monosaturated fats.
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palmitoleic acid and oleic acid
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What are the two essential fatty acids? Which is the omega-3 fatty acid?
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linoleic acid and alpha-linolenic acid (the precursor for omega-3 fatty acid)
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Which fat is the precursor the prostoglandins?
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w-6 arachidonic acid
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What are the symptoms of essential fatty acid deficiency?
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scaly dermatitis (ichthyosis) and visual and neurologic abnormalities
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What is a glycerolphospholipid?
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Phospholipds that contain glycerol
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What is a cardiolipin? Where is it found?
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Two molecules of phosphatidic acid (PA) esterified through phosphate groups to an additional molecule of glycerol.
Cardiolipins are found in bacteria and eukaryotes. |
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How does the platelet-activating factor differ from glycerolphospholipids?
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It is a glycerolphospholid with a saturated alkyl group in an ether link to carbon 1 and an acetyl residue instead of a fatty acid.
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What is the abbreviation for dipalmitoylphosphatidyl choline?
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DPPC
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What is the role for DPPC?
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It is the major lipid component of lung surfactant.
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What is RDS?
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Respiratory Distress Syndrome, insufficient surfactant production and/or secretion, sometimes seen in preterm infants, or adults after an infection or trauma.
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What does PG (prostaglandin) stand for? Functions?
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F-vasoconstriction, contraction of smooth muscle, uterine contractions; E-vasodilation, relaxes smooth muscle, induce labor
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What does TX (thromboxane) stand for? Functions?
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promotes platelet aggregation, vasoconstriction, mobilizes intracellular calcium, contraction of smooth muscle
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What does LT (leukotriene) stand for? Functions?
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increased chemotaxis of polymorphonuclear leukocytes, release of lysosomal enzymes and adhesion of white blood cells
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Arachidonic acid is the precusor for both 5-lipoxygenase and COX. Which pathway is enhanced in the pathophysiology of asthma?
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5-lipoxygenase
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What is COX?
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fatty acid cyclooxygenase, an isoenzyme
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What compounds inhibit COX-1 and 2?
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aspirin, indomethacin and phenylbutazone (all NSAIDs)
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What is the importance for a selective COX Inhibitor?
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They reduce pathologic inflammatory processes, such as pain, heat, redness, swelling and fever.
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What processes promote COX2 products?
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cytokines, endotoxin, growth factors, tumor promotors
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In the production of inflammatory lipid modulators, where do corticosteroids inhibit?
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Inhibits phospholipase A2 activity which in turn, arachidonic acid, the precursor of prostaglandins, is not made.
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What is prednisone?
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Prednisone is a synthetic corticosteroid drug that is particularly effective as an immunosuppressant drug. It is used to treat certain inflammatory diseases (such as moderate allergic reactions) and (at higher doses) some types of cancer, but has significant adverse effects. Because it suppresses the immune system, it leaves patients more susceptible to infections.
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What is the precursor for bile acids, steroid hormones and vitamin D?
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Progesterone
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Explain the pathophysiology of cholelithiasis (pg226).
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If there is more cholesterol than bile salts can break down, precipitates can develop in the gallbladder. Causes include malabsorption of bile acids, obstructed biliary tract, hepatic dysfunction, rapid recycling of bile acids or excessive biliary cholesterol secretion.
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Arrange the common plasma lipoprotein particles on the basis of size and density.
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From smallest size/highest density to largest size/lowest density: HDL, LDL, VLDL, chylomicron.
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What are the function of apolipoproteins?
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They are proteins that bind lipids to form lipoproteins, serving as activators or coenzymes, and provide recognition sites for cell-surface receptors.
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In general terms, provide and overview of the metaboloism of chylomicrons and VLDL.
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Chylomicrons, assembled in the intestinal mucosal cells, carry dietary triacylglycerol, cholesterol, fat-soluble vitamins and cholesterol esters to peripheral tissues.
VLDL, produced in the liver, carry endogenous triacylglycerol from the liver to peripheral tissue. |
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What is the difference between APO B-48 and APO B-100?
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APO B-48 is exclusive to chylomicrons and synthesized on rough ER.
APO B-100 is synthesized in the liver and found in VLDL and LDL. |
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What is the role for HDL, the good cholesterol?
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HDL is responsible for reverse cholesterol transport by removing cholesterol from the peripheral cells and transporting it back to the liver for excretion or re-utilization.
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What reaction is catyalyzed b lipoprotein lipase and how is it activated?
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It is activated by APO C-II and it hydrolyzes triacylglycerol contained in chylomicrons into free fatty acids and glycerol.
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What is the role of oxidized liproteins in plaque formation?
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Consumed by macrophages to form foam cells.
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What are scavenger receptors?
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Nonregulated receptors that can bind a wide range of ligands and take up (endocytosis) of modified LDL in the process of plaque formation.
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What is a foam cell?
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Macrophages that have consumed oxidized lipoproteins to form atherosclerotic plaque.
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What are cytokines?
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Signaling molecules, and are released by foam cells during plaque formation.
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How does this process affect hemostasis?
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When a large amount of plaque accumulates in the blood vessels, it creates a higher risk of cardiovascular disease.
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Which steroid is the common precursor for glucocorticoids, mineralcorticoids and sex hormones?
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Cholesterol
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Which organs synthesize and secrete which hormones?
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Adrenal cortex secretes cortisol, aldosterone and androgens.
Ovaries and placenta secrete estrogen and progestins. Testes secrete testosterone. (Pg 237) |
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What is the role for transcortin?
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Corticosteroid-binding globulin responsible for transporting globulin.
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What is the role for sex hormone binding globulin (SHBG)?
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A glycoprotein that binds to sex hormones, to be specific, androgens and estrogens. (Wiki)
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What enzyme system catalyzes hormone synthesis?
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Cholesterol side-chain cleavage enzyme complex
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What is CAH?
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Congenital Adrenal Hyperplasia
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When one path is blocked, for example with 21 alpha-hydroxylase deficiency (the most common CAH), what is the phenotype?
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Results in an overproduction of androgens leads to masculization of external genitalia in females and early virilization in males.
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What is the role for aromatase inhibitors?
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Used in the treatment of estrogen-responsive breast cancer in post-menopausal women.
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What is the role for releasing factors?
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In response to severe stress, corticotrophin-releasing hormone (CRH), produced by the hypothalamus, activates adrenocorticotropic hormone (ACTH).
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Which pituitary hormones affect which steroid hormone synthesis?
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Luteinizing hormone stimulates testosterone and estrogen/progesterone synthesis.
Follicle-stimulating hormone stimulates estrogen in females and androgens in males. ACTH stimulates secretion of glucocorticoids. |
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What is the function of cortisol?
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Increases gluconeogenesis, produces anti-inflammatory action and aids in protein breakdown in muscle.
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Function of aldosterone?
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Stimulate renal reabsorption of Na+ and excretion of K+.
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Function of estrogens?
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Controls menstrual cycle, promotes development of female secondary sex characteristics.
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Function of progesterone?
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Secretory phase of uterus and mammary glands.
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Function of testosterone?
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Stimulates spermatogenesis, promotes development of male secondary sex characteristics, promotes anabolism and masculinization of the fetus.
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What is the mechanism of steroid hormone action?
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Each steroid hormone diffuses across plasma membrane of target cell and binds to specific receptor. This receptor-ligand complex causes promoter activation and increased transcription of target genes.
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What is HRE?
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Hormone response element
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