Schild (apparent pA2) analysis of a kappa-opioid antagonist in Planaria.
Previous investigators have provided radioimmunological and immunocytochemical evidence for an enkephalinergic (opioid) system in Planaria and described naloxone-sensitive qualitative behavioral responses to kappa-opioid receptor agonists. We report the application of Schild-analysis to the antagonism of a selective kappa agonist (U-50,488H) by a selective kappa antagonist (nor-BNI) in a quantitative in vivo endpoint. The results provide further evidence of a kappa-opioid-like receptor in planarians.
Raffa
Robert B
RB
Department of Pharmaceutical Sciences, Temple University School of Pharmacy, 3307 N. Broad Street, Philadelphia, PA 19140, USA. robert.raffa@temple.edu
Baron
David A
DA
Tallarida
Ronald J
RJ
D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer / Q000494:pharmacology*; D000465:Algorithms; D018712:Analgesics, Non-Narcotic / Q000494:pharmacology; D000818:Animals; D004305:Dose-Response Relationship, Drug; D008124:Locomotion / Q000187:drug effects; D009271:Naltrexone / Q000031:analogs & derivatives* / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D010932:Planarians / Q000187:drug effects* / Q000502:physiology; D017473:Receptors, Opioid, kappa / Q000037:antagonists & inhibitors* / Q000502:physiology; D012044:Regression Analysis
D018712:Analgesics, Non-Narcotic; D009292:Narcotic Antagonists; D017473:Receptors, Opioid, kappa; C051844:norbinaltorphimine; D009271:Naltrexone; D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer