we have investigated the binding characteristics of two tritiated enkephalin analogues [ d-ala2-mephe4-glyol5 ] enkephalin ( dago ) and [ d-pen2 , d-pen5 ] enkephalin ( dpdpe ) which are highly selective for mu and delta opioid sites respectively , in homogenates of whole rat brain and of the pons/medulla region .
C0014298
enkephalin
C0525856
dpdpe