Squire Flashcards
Hematocrit
Portion of blood volume that is occupied by RBC
Plasma concentration
Albumin: 55% for oncotic pressure, lipid/steroid/hormone/NO transport, antioxidant protein with electrophile cysteine
Globulins: 38% transport ions, hormones and immune functions (gamma globulin)
Fibrinogen for clotting
Regulator proteins
a1-antitrypsin
Serpin= serine protease inhibitor protective during inflamation. Inactivated by cigarette smoke can result in elastase activity= emphysema and COPD
a1 antichymotrypsin
(serpin): serine protease inhibitor with protective role during inflammation.
serum amyloid A a1
Part of high-density lipoproteins that are secreted by liver in response to inflammatory cytokines; functions to recruit immune cells.
lipoprotein a1
Part of low-density and high-density lipoproteins enabling fats to be transported to adipocytes and liver in blood stream.
Haptoglobin a2
binds free hemoglobin for removal by spleen. Used to monitor for hemolytic anemia. Keeps hemoglobin
α2-macroglobulin
inhibits ALL classes of proteases, including those involved in coagulation (e.g., thrombin) and fibrinolysis (e.g., plasmin, kallikren)
ceruloplasmin
major copper carrying protein
thyroxine-binding globulin
binds thyroid hormones T3 and T4 (along with transthyretin and albumin
α2-antiplasmin
serpin responsible for inactivating plasmin (fibrinolys
protein C
zymogen that upon activation (proteolysis) acts to inactivate blood clotting (FVa and FVIIIa) and plasmin (fibrinolysis
angiotension:
upon proteolysis by ACE generates peptide hormone (vasoconstriction).
β2-microglobulin
: regulates iron transport following binding to receptor (activation
plasminogen
zymogen that upon activation (proteolysis) degrades fibrin (fibrinolysis).
transferrin:
high-affinity iron binding protein (2 binding sites) that transports iron through the body
C02 heme binding
Binds to amino terminus histidine and blocks O2 from binding via Bohr effect
Only 20% bound, the rest carried as carbonate
O2 binding
02 binds to heme and makes it planar, this moves the FG loop to change the other SU.
Bohr effect
(T) hb + 4O2 Hb(O2)4 + n H (R)
pka=7.7 pka=7.3
Salt bridge Asp-94 and His146 (stabilize deoxy form)
Deoxy has more salt bridges
More acidic the blood, the lower the saturation curve. So increasing CO2 increase H that decreases the saturation curve.
Protonation stableizes deoxy form
BPG and heme
Increases in hypoxia to increase O2 delivery
Allosteric effector and stabilizes deoxy form (T)
Higher the altitude, more BPG, more right shift
CO binding
Binds to the iron with higher affinity
Lose the sigmoidal curve with lowered vmax
Fetal heme differences
BPG binding cleft (Ser to His) mutation
EPO
Hypoxic stress enduces—more RBC
Synthesized in renal cortex
Hypoxia inducing factor always on but O2 degrades it.
Heme synthesis
Begins and ends in Mitochondria
Heme blocks first step of rxn
Hemoglobin pathologies
Thalassemias- Globin chain amount defect, common
Porphyrias- Porphorin ring problem, uncommon
Iron deficiency- most common
Sickle cell
Normal RBC lifespan- 120 days
Sickle- 10 days
Dehydration can cause nucleation event
Glu-Val at position 6
Heme catabolism
Processing and Excretion of Hydrophobic Products of Porphyrin Ring (Bilirubin)
Iron metabolism
Transferrin is Critical for Iron Transport and Delivery, binds 2 irons (high affinity, releases in acidic environment, used for Fe Def. assay)
Ferritin is Major Protein for Iron Storage (Liver, Epithelial, Macrophages; NOT Significant in RBCs. Binds 4500 Fe and looks like a bag ofrust of Fe3+.
Hepcidin
Peptide Hormone Made in Liver
Binds to Iron Export Channel Ferreportin to Block Uptake and Mobilization
Beta Thalassemia is Common Anemia Related to Iron Overload That May Result From Hepcidin Deficiencies
