Plasma Proteins Flashcards
What are the normal types of hemoglobin?
-HbA (97%)
-HbA2 (2%)
-HbF (1%)
-HbA1c - undergoes glycosylation depending on plasma glucose elevels - high in patrients w dm
What are 3 abnormal Hbs?
-Carbxy-Hb - CO replaces O2 amd binds 200X tighter than O2 - in smokers
-Met-Hb - contains oxidised ion, ferric ion, Fe3+ that cant carry O2
-Sulf-Hb - forms due to high sulfur levels in blood
What causes sickle cell disease?
Single gene mutation in ß-globin gene
-Glutamic acid at position 6 in HbA is replaced by valine
What are the major types of proteins in the plasma?
Albumin, globulins, fribrinogens
Characteristics of albumin?
-Most abundant protein produced by liver
-Soluble and monomeric
-Hlaf life approx. 20 days
-Synthesised as a pre-proprotein - pre-proalbumin
-3 domains w diff functions
-Ellipsoidal shape
Func of albumin?
-Maintains osmotic pressure
-Transports materials
-Competively binds calcium ions (Ca2+)
-Buffers pH
-Prevents photo-degradation of folic acid
What can low blood albumin levels be caused by?
-Liver disease
-Excess excretion by kidneys - nephrotic syndrome
-Burns
-Redistribution
-Acute disease states
-Mutation causing an albuminemia
What are high blood albumin levels caused by?
-Severe or chronic dehydration
-Retinol (vitA) deficiency
-High protein diets
How is albumin analysedß
-Add albumin to Bromcresol (green)
-Turns to blue - intensity of colour associated w conc
Globulin characteristics
-Higher molecular weights and water solubility than albumins
-Made of diff types of proteins called alpha, beta and gamma
-Some made by liver and some by immune system
What fractions can globulins be separated into on the basis of their electrophoretic mobility and sedimentation coefficient?
- alpha1-globulin = alpha1-Fetoprotein and alpha1-Antitrypsin
- alpha2-globulin = alpha2-Fetoprotein and Haptoglobin
- ß-Globulin = Transferrin and Ceruloplasmin
- Gamma -Globulin = Antibodies - IgA, IgG, IgM, IgE
What are high globulin levels caused by?
-Chronic inflammatory disease
-Bone marrow disorders - multiple myeloma
-Leukemias
-Autoimmunity - systemic lupus, collagen disease
-Rheumatoid arthritis
-Liver disease
-Carcinoid syndrome
-Ulcerative syndrome
-Kidney disease
-Chronic infections - HIV
What are low globulin levels caused by?
-Hepatic dysfunction
-Celiac disease
-IBS
-Acute hemolytic anemia
-Proteins not digested or absorbed properly
-Hypogammagloibulinemia
-Renal disease
What is transferrin?
-A ß-globulin
-Binds free iron in serum
-Normally 1/3 saturated w iron
When are transferrin levels decreased / increased?
Decreased : liver disease, chronic infections, nephrosis, congenitalatransferrinaemia
Increased : increased transferrin synthesis caused by iron deficieny anemia
