caa a22 4500 465737374 CHVBK 20180323111758.0 cr unu---uuuuu 170327e19901201xx s 000 0 eng 10.1007/BF02247126 doi (NATIONALLICENCE)springer-10.1007/BF02247126 Interactions between mu and kappa opioid agonists in the rat drug discrimination procedure [Elektronische Daten] [S. Negus, Mitchell Picker, Linda Dykstra] The present study was designed to explore the nature of the interaction between mu and kappa opioid agonists in the rat drug discrimination procedure. In rats trained to discriminate the kappa agonist U50,488 (5.6 mg/kg) from water, the other kappa agonist bremazocine substituted completely for the U50,488 training stimulus, and the additional kappa agonist tifluadom substituted in three of five of rats tested. In contrast, the mu agonists morphine, fentanyl, and buprenorphine produced primarily vehicle-appropriate responding. When morphine, fentanyl, and buprenorphine were combined with the training dose of U50,488, all three mu agonists reduced U50,488-appropriate responding. In rats trained to discriminate the mu agonist morphine (10.0 mg/kg) from saline, the other mu agonists morphine and buprenorphine all substituted in a dose-dependent manner for the morphine training stimulus, whereas U50,488, bremazocine, and tifluadom produced primarily vehicle-appropriate responding. When combined with the training dose of morphine, bremazocine antagonized morphine's discriminative stimulus effects, whereas U50,488 and tifluadom had no effect. The barbiturate pentobarbital neither substituted for, nor antagonized, the discriminative stimulus effects of either U50,488 or morphine. These results suggest that mu agonists and kappa agonists produce interacting effects in the drug discrimination procedure in rats. Springer-Verlag, 1990 Morphine nationallicence Fentanyl nationallicence Buprenorphine nationallicence U50,488 nationallicence Bremazocine nationallicence Tifluadom nationallicence Drug discrimination nationallicence Opioid interactions nationallicence Negus S. Curriculum in Neurobiology, University of North Carolina, 27599, Chapel Hill, NC, USA aut Picker Mitchell Department of Psychology, University of North Carolina, 27599, Chapel Hill, NC, USA aut Dykstra Linda Department of Psychology, University of North Carolina, 27599, Chapel Hill, NC, USA aut Psychopharmacology Springer-Verlag 102/4(1990-12-01), 465-473 0033-3158 102:4<465 1990 102 213 https://doi.org/10.1007/BF02247126 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02247126 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Negus S. Curriculum in Neurobiology, University of North Carolina, 27599, Chapel Hill, NC, USA aut NATIONALLICENCE 700 1- Picker Mitchell Department of Psychology, University of North Carolina, 27599, Chapel Hill, NC, USA aut NATIONALLICENCE 700 1- Dykstra Linda Department of Psychology, University of North Carolina, 27599, Chapel Hill, NC, USA aut NATIONALLICENCE 773 0- Psychopharmacology Springer-Verlag 102/4(1990-12-01), 465-473 0033-3158 102:4<465 1990 102 213 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer