by using a constant-rate , fixed concentration intrathecal infusion model , the time course of change in hot plate ( hp ) response latencies over a 7-day period was examined in rats receiving constant infusion of saline ( vehicle ) , morphine ( mor ( 2 , 6 or 20 nmol/hr ) , sufentanil ( suf ) ( 0.06 , 0.2 or 0.6 nmol/hr ) , d-ala2-mephe4-gly-ol5-enkephalin ( damgo ) ( 0.1 , 0.3 or 1.0 nmol/hr ) ( mu opioids ) , d-ala2-d-leu5-enkephalin ( dadle ) ( 2,6 or 20 nmol/hr ) ( delta opioid ) , st-91 ( 3 , 10 or 30 nmol/hr ) ( alpha-2 agonist ) or the combination of st-91 + mor .
C0525773
damgo
C0014298
enkephalin