Term
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Definition
- biconcave disc
- generates more surface area than sphere
- mean corpuscular volume (MCV)- 87 cubic microns
- diameter- 7 microns
- major content is Hb
- Mean Corpuscular Hb Conc. (MCHC) of 33% (very concentrated solution of Hb)
- MCH- how much Hb is in one RBC (absolute number) is 30 picograms/cell
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Term
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Definition
how many RBC's in a given volume of blood (average value = 5-5.5 x 10^-12 cells/L)
Female count is usually lower than male. |
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Term
Difference btw plasma and serum |
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Definition
- plasma- has clotting factors
- serum- no clotting factors
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Term
Describe the gradation of centrifuged blood |
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Definition
- at top, you will see the plasma or serum
- at bottom, you will see packed cells
If you measure volume of packed cells over total volume, you find hematocrit. |
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Term
How is Hb concentration determined |
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Definition
lyse the red blood cells and see the amount of Hb released in sample of blood
(average 16 grams/deciL) |
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Term
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Definition
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carry molecular oxygen from the lungs to the peripheral tissue via protein Hb
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bind CO2 and take it to the lungs
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buffer (transport of CO2 in plasma as bicarb.)
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Term
Driving force of binding of oxygen to Hb |
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Definition
partial pressure of oxygen (dont forget oxygenated Hb is a stronger acid than deoxygenated) |
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Term
Mechanism of formation of meth Hb |
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Definition
- Hb-O2 dissociates to form superoxide anion and met-Hb
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Term
Mechanism of converting met-Hb to Hb |
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Definition
- Met Hb and cyc b5 (carry ferrous) goes to Hb via Met Hb reductase
- cyc b5 (carrying ferric at the end of reaction) converted back to ferrous form via cyc b5 reductase (requires oxidation of NADH)
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Term
Mechanism of inactivating superoxide anion formed by making met-Hb |
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Definition
- 2 superoxide anions and water produces oxygen and hydrogen peroxide via superoxide dismutase
- 2 hydrogen peroxides generates oxygen and 2 waters via catalase (hemeprotein)
Superoxide dismutase is in almost ALL cells. |
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Term
Effect of oxidant on plasma membrane |
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Definition
- oxidant can oxidize the double bond in polyunsaturated fatty acids found in the membrane to a lipid peroxide
- peroxides will break down to form free radicals
- if this is not stopped, chain reactions that cause loss of membrane integrity
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Term
Structure and functino of tocopherol (Vit. E) |
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Definition
- structure- has a very long isoprenoid side chain with two connected ring structures
- function
- in reduced form, serves as antioxidiant (reducing agent) and inactivate oxidants (reduce it to alcohol) non-enzymatically
- produces oxidized form of Vit E
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Term
Compounds that can reduce vitamine E |
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Definition
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Term
Structure and function of glutathione system reducing vitamin E |
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Definition
- tripeptide (glu, cys, gly)
- SH group of Cys supplies reducing equivalents and its oxidized to the disulfide
- function- reduce Vit E under non enzymatic conditions
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Term
Function, location of glutathione peroxidase |
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Definition
- location- can be associated with the membrane or in the cytosol
- function (requires sellinium)
- catalyze reduction of lipid peroxides using glutathione as reducing agent
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Term
Function and structure of glutathione reductase |
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Definition
- structure- flavoprotein
- function
- catalyze reduction of oxidized glutathione into reduced form (now it can eliminate lipid peroxides)
- oxidizes NADPH to NADP (NEED HMG SHUT TO KEEP THIS RXN GOING)
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Term
Mechanism of RBC maintaining ionic balance |
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Definition
- w/o balance, cell will swell or shrink
- maintained via ion pumps
- Na/K pump (translocase)
- uses half of ATP generated by RBC
- ATP production via substrate level phosphorylation steps of glycolysis (3 PG kinase and pyruvate kinase)
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Term
Sequence of Rapoport Luebering Shunt |
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Definition
- 1,3 BPG goes to 2,3 BPG via mutase
- 2,3 BPG goes to 3-PGA via phosphatase
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Term
Describe role of HMG Shunt in production of glycolytic intermediates |
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Definition
- oxidative pathway will produce the NADPH needed for glutathione reductase to form reduced glutathione and Ru-5P
- NADPH via G6PDH and 6PGDH
- can speed up to meet the need of glutathione reductase
- Ru-5P uses non oxidative pathway to form F6P via transketolase, transaldolase, and transketolase again
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Term
Enzyme deficiencies that cause hemolytic anemia and how they kill RBCs? |
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Definition
- G6P dehydrogenase (no NADPH for glutathione reducatse, so the cell is killed by oxidants)
- pyruvate kinase (ATP cannot be provided to translocase needed to maintain ionic balance
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Term
RBC values for patient with G6P DH deficiency (these values are indicative of any hemolytic anemia) |
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Definition
decrease RBC count
decrease Hb conc.
decrease Hct
normal MCV
normal MCHC
normal MCH
nothing wrong with volume or Hb in RBC |
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Term
classifications of anemia and their definitions |
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Definition
- normocytic normochromic
- volume normal
- color of RBC normal
- microcytic hypochromic
- low MCV, MHC
- not much color (usually when RBC's are small, there is not much color to them)
- macrocytic normochromic
- high MCV/MHC
- normal color to RBC
Based on volume |
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Term
RBC values of PK deficiency |
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Definition
Normocytic normochromic anemia
- decrease RBC count
- decrease Hb conc.
- decrease Hct
- normal MCH, MCV
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