Protein storage (Labile protein)
The disorganized
protein present in liver, thymus, prostate. Seminal vesicles, alimentary tract,
pancreas, spleen and kidneys, etc., are drawn upon to meet the need of the body
in case of shortage of proteins in diet as in case of starvation and these
proteins are called labile proteins. These are utilized for the synthesis of
other proteins and may be oxidized to provide energy when required.
End
products of protein metabolism
The nitrogen released
from amino acid (protein) catabolism is excreted from the body in forms which
vary in different species of animals. The considerable amount of nitrogen
excreted through the urine is urea.. The human also excretes nitrogen of purine
bases as uric acid. Creatine excretion is exclusively from tissue protein
breakdown. Neutral sulphur excretion does not indicate the nature of dietary or
tissue protein breakdown.
Due to dynamic state of
amino nitrogen of amino acid and differential pattern of metabolism of labile
protein, the excretion of different nitrogenous metabolic end products does not
always give real metabolic picture of protein metabolism. Increased creatine
excretion may indicate increased tissue protein break down, i.e. specially
muscle protein catabolism going on. Increased uric acid excretion may be due to
increased purine catabolism. Increased urea excretion may indicate increased
dietary protein catabolism.
End
products of exogenous protein metabolism
No comments:
Post a Comment