k+-evoked outflow of serotonin was inhibited significantly up to 50 % in the presence of the mu-selective agonist [ d-ala2 , n-methyl-phe4 , gly5-ol ] enkephalin ( dago ) and of the delta-selective agonist [ d-pen2 , d-pen5 ] enkephalin ( dpdpe ) .
C0014298
enkephalin
C0525856
dpdpe