Term
| insulin's mechanism of action |
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Definition
| moves GLUT-4 transporter to membrane so that glucose can enter; glut 4 is found in adipose tissue, muscle, and heart |
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Term
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Definition
| expressed in tissues w/ barriers (brain, testes, placenta, etc) |
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Term
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Definition
| major transporter channel for glucose in CNS |
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Term
| hexokinase vs glucokinase |
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Definition
1.both catalyze glu to glu-6P reaction
2.hexokinase - found in all tissues; low Km (high affinity); negatively regulated by G6P
3.Glucokinase - found in liver; high Km (works only when lots of glucose); stimulated by insulin |
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Term
1. rate limiting reaction in glycolysis is what?
2. what are the regulators of this rxn? |
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Definition
1. F6P to F1,6biP catalyzed by PFK-1
2. look at p94 of BRS (great diagram)
Positive: AMP and F2,6biP (catalyzed by PFK-2)
Negative: ATP and citrate |
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Term
| Phosphofructokinae dificiency |
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Definition
1.type of glycogen-storage disease
2. glycogen accumulates in muscles, results in inefficient use of glucose stores by RBCs and muscle
3. Sxs: hemolytic anemia and muscle cramps |
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Term
| pyruvate kinase deficiency results in what most prominent feature |
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Definition
| hemolytic anemia (since RBCs don't have mts, they rely on glycolysis for ATP production) |
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Term
| how does NADH produced by glycolysis get passed on to electron transport chain? |
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Definition
| it's produced in the cytosol, and can't enter mt on its own, so it uses 2 shuttle systems: glycerol phosphate (FADH2 is the final product) and malate-aspertate shuttle (NADH is the final product) |
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Term
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Definition
| inhibits pyruvate dehydrogenase complex needed to oxidize pyruvate to acetyl-coA, and thus begin TCA cycle |
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Term
| pyruvate dehydrogenase complex deficiency |
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Definition
| one of most common neurodegenerative disorders; severe forms are lethal; mild forms display ataxia, lactate buildup, psychomotor delays |
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Term
| what controls the the TCA cycle's speed? at which step? by what mechanism? |
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Definition
ADP vs ATP concentration
-high ADP levels - ADP allosterically activates isocitrate dehydrogenase, and the cycle speeds up
-high ATP levels, NADH builds up, and allosterically inhibits isocitrate dehydrogenase |
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Term
| pyruvate carboxylase deficiency |
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Definition
| blocks conversion of puryvate to oxaloacetate; results in build-up of lactic acid (more pyruvate being converted to it)...presents early in life w/ muscle weakness, ataxia, seixures, vomitting |
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Term
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Definition
found in beta cells; glucose enters through these to begin the pathway that ends in insulin secretion (blockade of K channel and build-up of Ca are intermediate steps)
-also found in nerves and endothelium; insulin independent glucose uptake |
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Term
| what is the rate-limiting step in synthesis of cholesterol? |
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Definition
| HMG-CoA reductase converts HMG-CoA to Mevalonic acid |
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Term
| mechanism of action of statin drugs |
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Definition
| block HMG-CoA reductase - de-novo cholesterol (80% of cholesterol in body) can't be made, so LDL receptors are upregulated and cholesterol is taken up by cells from blood |
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Term
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Definition
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Term
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Definition
| on VLDL formed in epithelilial cells |
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Term
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Definition
-found on HDL
-activates LCAT |
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Term
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Definition
-added to chylomicrons by HDL
-ApoC IIactivates lipoprotein lipase |
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Term
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Definition
-added to chylomicrons by HDL
-recognition factor for cell surface receptors of VLDL and LDL |
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Term
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Definition
-breaks down TGs w/in chylomicrons
-activated by ApoC II
-induced by insulin |
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Term
1.Acyl-cholesterol Acyl-transferase (ACAT)
2. Lecithin-cholesterol Acyltransferase (LCAT) |
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Definition
1.w/in cells, esterifies cholesterol into cholesterol esters for storage in cells
2. w/in HDL, esterifies cholesterol into cholesterol esters - this is how cholesterol accumulates w/in HDL; activated by ApoA |
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Term
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Definition
catalyzes addition of alpha-hydroxul group to cholesterol as the rate-limiting step of bile-salt synthesis
-inhibited by bile acids |
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Term
| what's the rate-limitng step in bile-acid synthesis |
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Definition
| 7alpha-hydroxylase conversion of cholesterol to 7alpha-hydroxycholestrol |
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Term
| what amino acids (2) can bile salts be conjugated to? |
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Definition
1. glycine
2. taurine ( a drivative of cysteine) |
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Term
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Definition
-RET oncogene chromosome 10
1. Medullay thyroid cancer - almost all get it
2. pheochromocytoma - ~30% get it
3. Increased PTH secretion - ~5% get it |
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Term
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Definition
-RET oncogene chrom 10
1. parathyroid cacner
2. pituitary cancer
3. islet cell cancer - insulinoma for ex |
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Term
1. myosin light chain kinase (MLCK)
2. myosin light chain phsophatase |
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Definition
-both phosphorylate, dephosphorylate myosin light chain
1. active when de-phosphorylated - deactivates myosin light chain
2. actived when phosphorylated - deactivates myosin light chain |
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Term
Smooth muscle relaxation and...
1. cAMP
2. cGMP |
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Definition
1. activates PKA, which phosphorylates and thus inactivates myosin light chain kinase, so that it can't phosphorylate myosin light chain
2. helps phosphorylate and thus activate myosin light chain phosphorylase, which dephosphorylates myosin light chain
....look at pharm notes to see how drugs and PDE relate to this |
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Term
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Definition
converts arachidonic acid to leukotrienes (actually 1st to an inter-emdiart HPETEs), which then lead to bronchoconstriction
-blocked by COX inhibitors |
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Term
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Definition
-converts phospholipids to arachidonic acid
-blocked by corticosteroids |
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Term
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Definition
| converts testosterone to DHT |
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Term
| what happens on the biochemical level when ethanol is consumed? |
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Definition
1. alcohol dehydrogenase and aldehyde dehydrogenase require NAD and transfer elctrons to it, and thus make it NADH
2. This excess of NADH pushes puryvate to lactate and oxaloacetate to malate.
3. Both pyruvate and oxaloacetate are intermediates in gluconeogenesis
4. thus, the person ends up hypoglycemic |
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Term
1. pyruvate kinase
2. pyruvate dehydrogenase
3. pyruvate carboxylase |
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Definition
1. PEP to pyruvate
2. pyruvate to acetyl coA (requires thiamine)
3. pyruvate to oxaloacetate (requires biotin) |
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Term
| carbamoyl phospate synthase I (CSP I) |
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Definition
1. rate-limiting step (and also 1st step) in urea cycle
2. deficiency, just like of any other urea cycle enzyme except for arginase, will cause hyperammonemia |
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Term
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Definition
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Term
| albuminocytologic dissociation |
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Definition
| GBS (elevated CSF protein w/ normal cell count) |
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Term
| tumbling motility of a microbe |
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Definition
1. listeria monocytogenes
2. trichomonos vaginalis |
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Term
| optochin sensitive gram pos coccus |
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Definition
| s. pneumo (alpha hemolysis) |
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Term
| bacitrasin sensitive gram pos coccus |
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Definition
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Term
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Definition
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Term
| what organism can cause hypoglycemia? how? |
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Definition
| B. pertussis - activates islet cells (insulin release) |
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Term
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Definition
| cause of osteomyelitis in sickle cell pts |
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