Creatine kinase Flashcards
In what tissues is CK present at high levels
In brain cells, myocardial cells and skeletal muscle cells, because these are metabolically active tissues
When and why is CK found in the blood
Creatine kinase can be found in blood when cells are damaged and die, causing its contents to be released into the blood
What causes the plasma membrane of myocardial cells to become leaky
Hypoxia can lead to imbalance of ion concentration gradients that are normally actively maintained. Ion imbalance causes metabolic processes in cell to stop and cells to die, leading to leaking of plasma membranes of cells like myocardial cells
How might you determine CK activity
Creatine kinase activity can be measured using a coupled assay involving photospectometry of NADP and NADPH, involving conversion of creatine phosphate to creatine, glucose to glucose-6-phosphate and ADP to ATP
Why might the three isoenzymes be separated by electrophoresis
The monomers in the dimer creatine kinase, B or M, differ in charge because of different AA residues, so isoenzymes BB, BM, MM can be separated by charge in electrophoresis
How might one establish a diagnosis of myocardial damage
If in electrophoresis known samples of isoenzymes BM, MM and BB are used, sample from blood could be compared to see is creatine kinase from myocardial tissue is present in blood
Does an increase in serum CK activity relate to the size of myocardial damage?
Yes, because myocardiocytes contain roughly the same amount of creatine kinase per cell, so the more creatine kinase in blood the more cells have died
What is the time course of serum CK after a myocardial infarction?
Creatine kinase can be found in high concentrations in blood between 12 hours and 2 days after myocardial infarction
What other markers can be used for diagnosis of myocardial damage?
The serum concentrations of serum glutamate oxaloacetate transaminase and lactate dehydrogenase
