atp at a concentration of 100 microm and the opioids , methionine enkephalin , beta-endorphin , dynorphin , [ d-ala2 , n-me-phe4 , gly5-ol ] -enkephalin , [ d-ala2-d-leu5 ] -enkephalin and morphine at concentrations between 10 pm to 1 microm did not activate o2- formation .
C0014295
methionine enkephalin
C0014298
enkephalin