in this study motor effects of dynorphin 1-17 , its n-terminal fragments d-pen2 , d-pen5-enkephalin ( dpdpe ) and d-ser2- [ leu5 ] enkephalin-thr ( dslet ) without or with pretreatment with naloxone , ( - ) -2- ( furylmethyl ) -noretacocine ( mr 2266 ) or tetrodotoxin ( ttx ) on the isolated rat colon were compared with those of nonpeptide kappa opioid receptor agonists .
C0525856
dpdpe
C0014298
enkephalin