the membrane was hyperpolarized by the opioid peptides tyr-d-ala-gly-mephe-gly-ol ( dagol , 0.01-1 microm ) and [ met5 ] enkephalin ( 3-30 microm ) , though not by tyr-d-pen-gly-phe-d-pen and u50488 .
C0525773
dagol
C0014298
enkephalin