to elucidate the physiological and pathophysiological significance of methionine- and leucine-enkephalin ( met-and leu-enkephalin , respectively ) in human sympathoadrenal system , the contents of these peptides in normal human sympathetic nervous system , adrenal medulla , and pheochromocytomas were determined by specific radioimmunoassays combined with reverse-phase high-performance liquid chromatography .
C0039044
sympathetic nervous system
C0001629
adrenal medulla