RELATIONSHIP BETWEEN PLASMA CATECHOLAMINE LEVELS AND PHARMACODYNAMICS IN NORMAL SUBJECTS

Abstract

Catecholamine (noradrenaline or adrenaline) and saline were administered subcutaneously to 27 male healthy medical students and relationship between plasma catecholamine levels and pharmacodynamics were studied. Plasma noradrenaline level significantly increased from 1.78±0.28 to 11.29±2.98 pmol/ml at 5 min after 0.4mg of noradrenaline injection. Plasma adrenaline level also significantly increased from 0.28±0.06 to 1.37±0.26 pmol/ml at 5 min after 0.3 mg of adrenaline injection. Systolic and diastolic blood pressure increased and heart rate decreased significantly after noradrenaline administration. Significant increase in blood pressure after noradrenaline was due to increase in peripheral resistant depend on a-effect of noradrenaline. Significant decrease in heart rate after noradrenaline was though to be vagal reflex. T wave hight on E. C. G. decreased significantly after adrenaline administration. Significant decrease in T wave hight after adrenaline was thought to be due to direct effect of adrenaline on the membrane of cardiac muscle cell.