Serum Proteins and associated disorders - Part 1 Flashcards
Objectives: i.Describe how plasma proteins can be separated by electrophoresis and classify plasma proteins based on electrophoreticmobility ii.Describe the functions of serum albumin and globulins iii.Indicate the role of proteins of the complement system iv.Predict the common causes of hypoalbuminemia(liver disease, nephroticsyndrome, protein malnutrition) and explain the biochemical basis for the occurrence of edema in hypoalbuminemia v.Distinguish the functions of proteins that are foun
What is the difference between serum and blood plasma?
Serum does not have clotting factors
Which serum protein travels most towards the cathode during electrophoresis?
Gamma globulin band
List the serum proteins in the order they go from anode to cathode during electrophoresis?
Albumin, alpha 1, alpha 2, beta, gamma globulin
At what pH is electrophoresis performed for serum proteins?
8.6
In electrophoresis, separation is due to _______________
Charge NOT function
What proteins synthesized by the liver are found in the Alpha1 band in a densiometry reading?
alpha1-antitrypsin
a fetoprotein
transcortin
Which proteins synthesized by the liver are found in the alpha2 band in a densiometry reading?
Alpha2-macroglobulin
Ceruloplasmin
Hepatoglobin
Which proteins synthesized by the liver are found in the Beta band in a densiometry reading?
Transferrin
Hemopexin
B lipoprotein
Which proteins synthesized by plasma cells are found in the gamma band in a densiometry reading?
Immunoglobulins: IgG IgM IgA IgD IgE
What is the pH of albumin?
Anionic at pH 7.4
What happens when serum albumin levels are low?
There is an increased amount of water in the interstitial space, resulting in edema
List the serum proteins in the order they go from anode to cathode during electrophoresis?
Albumin, alpha 1, alpha 2, beta, gamma globulin
At what pH is electrophoresis performed for serum proteins?
8.6
In electrophoresis, separation is due to _______________
Charge NOT function
What proteins synthesized by the liver are found in the Alpha1 band in a densiometry reading?
alpha1-antitrypsin
a fetoprotein
transcortin
Which proteins synthesized by the liver are found in the alpha2 band in a densiometry reading?
Alpha2-macroglobulin
Ceruloplasmin
Hepatoglobin
Which proteins synthesized by the liver are found in the Beta band in a densiometry reading?
Transferrin
Hemopexin
B lipoprotein
Which proteins synthesized by plasma cells are found in the gamma band in a densiometry reading?
Immunoglobulins: IgG IgM IgA IgD IgE
What is the pH of albumin?
Anionic at pH 7.4
What happens when serum albumin levels are low?
There is an increased amount of water in the interstitial space, resulting in edema
In hypo-albuminemia, the colloid osmotic pressure is what?
Low
Where is albumin glycosylated?
Unlike other serum proteins synthesized in the liver, albumin is NOT glycosylated in the liver.
Albumin is non-enzymatically glycosylated in blood at high glucose levels.
What type of bonds stabilize albumin?
Internal disulfide bonds
Serum albumin levels can be used as an indicator for what?
- Nutritional status
- Liver synthetic function
What does the presence of albumin in the urine suggest?
Implies damage to the basement membrane of the kidney glomerulus
The binding of cations, such as Calcium, is influenced by what?
- Plasma pH
- increase in plasma pH leads to more negative charges in albumin (albumin has high amount of neg charges)
During fasting, albumin transports free fatty acids through what type of bonds?
Noncovalent
What is an example of a hormone carried by albumin?
Thyroxine
albumin is a reservoir for free hormone
What are some examples of drugs that can displace bilirubin from albumin, thus leading to kernicterus in infants?
Aspirin
Saliclyates
Sulfanomides
What are causes of hypoalbuminemia?
1) Decreased synthesis of albumin
a. Low protein diet (malnutrition)
b. Chronic liver disease (cirrhosis)
2) Increased loss of albumin
a. Severe burns
b. Loss of albumin in urine (nephrotic syndrome)
Alpha1-antitrypsin is also known as what?
alpha1-AT
alpha1-antiproteinase
What is the function of Alpha1-antitrypsin?
an inhibitory protein against neutrophil elastase in alveoli.
What is the role of transcortin?
Transport of cortisol
Which globulin proteins are synthesized in the liver?
albumin ,alpha and beta globulins
Where are gamma globulin synthesized?
plasma cells (B cells)
a1-AT exists in _________, patients with ________ can have a genetic defect.
–____ allele is the normal allele
–____ allele and __ allele are defective alleles
polymorphic forms emphysema M Z S
A low amount of a1-AT in the blood can lead to what? which is due to what?
- Emphysema
- due to destruction of elastin in lung
Individuals who are homozygous for the Z allele for a1-AT are at risk for developing what?
- Pulmonary disease
- Liver disease
How does smoking effect alpha1-AT activity?
- Smoking leads in general to increased neutrophil activity and to an increased amount of neutrophil elastase in the lungs
- Cigarette smoke oxidizes the methionine residue in a1-AT that is needed for binding to elastase. This reduces its efficacy to inhibit neutrophil elastase
