the selectivity sequence is : tryptamine ( 18.1 ) greater than phenylethylamine ( 11.6 ) greater than tyramine ( 2.4 ) greater than li+ ( 1 ) greater than serotonin ( 0.34 ) greater than epinephrine ( 0.09 ) greater than dopamine ( 0.05 ) greater than norepinephrine ( 0.02 ) , showing the ionophore to be more selective to li+ than to any of the neurotransmitters studied .
C0014563
epinephrine
C0028351
norepinephrine