Hematology and Oncology Book

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Red Blood Cell PhysiologyAka: Hemoglobin Production, Iron

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  1. Physiology: Erythropoietin
    1. Primary hormone regulator of RBC production
    2. Erythropoietin sources
      1. Fetus: Monocyte and Macrophage system in liver
      2. Postnatal: Peritubular cells in kidney
  2. Physiology: Iron
    1. Total Body Iron
      1. Men: 50 mg/kg (or 3.8 grams for 75 kg man)
      2. Women: 42 mg/kg (or 2.3 grams for 55 kg woman)
    2. Normal adult iron distribution
      1. Functional iron (70%)
        1. Hemoglobin component (80%)
        2. Myoglobin
        3. Intracellular respiratory enzymes (cytochromes)
      2. Storage or transport iron (30%)
        1. Ferritin (primary storage)
        2. Hemosiderin
        3. Transferrin (iron transport)
    3. Iron Loss
      1. Men and non-menstruating women: 1 mg iron/day
      2. Menstruating women: 1.6 to 2.5% more per day
        1. Blood loss varies widely per Menstrual Cycle
        2. Average loss: 10 mg iron/cycle
        3. Blood loss may approach 42 mg/cycle in heavy flow
      3. Pregnancy: 700 mg iron lost
      4. Whole blood donation (500 cc): 250 mg iron lost
  3. Physiology: Red Blood Cell
    1. Hemoglobin produced until amounts to 90% of RBC mass
    2. Red Blood Cells start as Reticulocytes in Bone Marrow
      1. Reticulocytes are juvenile Red Blood Cells
        1. Nucleus extruded once RBC has matured
        2. Reticulocytes contain ribosome remnants
          1. Immature Reticulocytes contain most ribosomes
          2. Mature Reticulocytes contain least ribosomes
      2. Reticulocytes have 4 day life span
        1. Bone Marrow: 3 days (less if Erythropoietin high)
        2. Peripheral blood: 1 day
    3. Red Blood Cell survival
      1. Normal RBC: 120 days
      2. Abnormal RBC: May survive as little as 15 days
      3. Following transfusion: RBC survival 2-3 weeks
  4. Physiology: Hemoglobin
    1. Heme protein complex of 2 pairs of polypeptides
    2. Six types of normal Hemoglobin
      1. Embryonic
      2. Gower I
      3. Gower II
      4. Portland
      5. Fetal Hemoglobin (HbF)
        1. Primary Hemoglobin in fetus
        2. Replaced by Adult Hemoglobin by age 6-12 months
      6. Adult Hemoglobin (HbA and HbA2)
  5. References
    1. (1998) MMWR Morb Mortal Wkly Rep 47:1
  6. Resources
    1. MMWR Iron Deficiency Anemia Prevention
      1. http://www.cdc.gov/mmwr/pdf/rr/rr4703.pdf

Iron (C0302583)

Definition (MSH)A metallic element found in certain minerals, in nearly all soils, and in mineral waters. It has the atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of hemoglobin, cytochrome, and other components of respiratory enzyme systems. Its chief functions are in the transport of oxygen to tissue (hemoglobin) and in cellular oxidation mechanisms. Depletion of iron stores may result in iron-deficiency anemia. Iron is used to build up the blood in anemia. (From Dorland, 27th ed)
Definition (CSP)metallic element found in certain minerals, in nearly all soils, and in mineral waters; atomic symbol Fe, atomic number 26, and atomic weight 55.85; it is an essential constituent of hemoglobin, cytochrome, and other components of respiratory enzyme systems; chief function is in the transport of oxygen to tissue (hemoglobin) and in cellular oxidation mechanisms.
Definition (PDQ)An element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. Check for "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=42183&idtype=1" active clinical trials or "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=42183&idtype=1&closed=1" closed clinical trials using this agent. ("http://nciterms.nci.nih.gov:80/NCIBrowser/ConceptReport.jsp?dictionary=NCI_Thesaurus&code=C598" NCI Thesaurus)
Definition (NCI)An element with atomic symbol Fe, atomic number 26, and atomic weight 55.85.
ConceptsPharmacologic Substance (T121) , Biologically Active Substance (T123) , Element, Ion, or Isotope (T196)
EnglishFe, Fe element, ferric ion, Iron, Iron agent, Iron preparation, Iron product
Spanishagente con hierro, hierro, preparado con hierro, preparado de hierro
CreditsDerived from the NIH UMLS (Unified Medical Language System)



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