during the evaluation of a modified radioenzymatic determination of plasma adrenaline and noradrenaline , it has been found that there exists a highly significant ( p less than 0.001 ) negative correlation between the amount of radioactivity incorporated in the internal standard added to plasma and the period during which the plasma had been stored at -25 degrees c , but only in plasma from patients with essential hypertension .
C0014563
adrenaline
C0028351
noradrenaline