Lecture 22- Enzymes of Diagnostic Importance
Lecture 22- Enzymes
of Diagnostic
Importance
, Lecture 22- Enzymes of Diagnostic Importance
What marker enzymes of diagnostics do we look for in the liver? What are
the names?: 1. Aspartate transaminase (AST)
1. Alanine transaminase (ALT)
2. Where are the liver enzymes localized, and describe their activity.:
Localization: ALT located in cytosol of hepatocytes exclusively; AST present in
cytosol and mitochondria of hepatocytes. It also expresses in muscle cells
(skeletal/cardiac muscles).
Activity: The activity of ALT in hepatocytes is very high when compared to AST 3.
What is the diagnostic importance of liver enzymes?: When liver cells are
damaged due to infections, inflammation etc (hepatitis, liver cirrhosis) abnormal
amounts of these 2 enzymes are released in the bloodstream. The levels of ALT
and AST serve as important markers of impaired liver function and play an
important role in assessing and monitoring the degree of hepatocyte damage in
the liver.
, Lecture 22- Enzymes of Diagnostic Importance
.
4. What is ALP? What are they important in? Where are they localized?
Where can they be present in high concentrations in?: Alkanline phosphatase
(ALP): is a group of enzymes that dephosphorylates proteins, nucleic acids and
alkaloids at a higher pH.
5. ALP as a SIGNIFICANT marker of what specific condition? Describe this
condition and its symptoms.: Cholestasis
6. In order to use enzyme markers for a clinical diagnosis, what must a
physician check for?Clinical Diagnosis of a Disease using Enzyme Markers:
1)
Presence/absence of marker enzymes in plasma/serum
2) Change in enzyme conc.: Plasma/serum/ cellular concentration (see if there
is a drastic change)
3) Change in enzyme localization-mitochondrial enzymes when mito is
damaged will be released into the blood 4) Pattern of enzyme clearance
Lecture 22- Enzymes
of Diagnostic
Importance
, Lecture 22- Enzymes of Diagnostic Importance
What marker enzymes of diagnostics do we look for in the liver? What are
the names?: 1. Aspartate transaminase (AST)
1. Alanine transaminase (ALT)
2. Where are the liver enzymes localized, and describe their activity.:
Localization: ALT located in cytosol of hepatocytes exclusively; AST present in
cytosol and mitochondria of hepatocytes. It also expresses in muscle cells
(skeletal/cardiac muscles).
Activity: The activity of ALT in hepatocytes is very high when compared to AST 3.
What is the diagnostic importance of liver enzymes?: When liver cells are
damaged due to infections, inflammation etc (hepatitis, liver cirrhosis) abnormal
amounts of these 2 enzymes are released in the bloodstream. The levels of ALT
and AST serve as important markers of impaired liver function and play an
important role in assessing and monitoring the degree of hepatocyte damage in
the liver.
, Lecture 22- Enzymes of Diagnostic Importance
.
4. What is ALP? What are they important in? Where are they localized?
Where can they be present in high concentrations in?: Alkanline phosphatase
(ALP): is a group of enzymes that dephosphorylates proteins, nucleic acids and
alkaloids at a higher pH.
5. ALP as a SIGNIFICANT marker of what specific condition? Describe this
condition and its symptoms.: Cholestasis
6. In order to use enzyme markers for a clinical diagnosis, what must a
physician check for?Clinical Diagnosis of a Disease using Enzyme Markers:
1)
Presence/absence of marker enzymes in plasma/serum
2) Change in enzyme conc.: Plasma/serum/ cellular concentration (see if there
is a drastic change)
3) Change in enzyme localization-mitochondrial enzymes when mito is
damaged will be released into the blood 4) Pattern of enzyme clearance
