title: Development of tolerance to the antinociceptive effect of morphine after intraventricular injection.
mesh_terms: D000818:Animals; D002247:Carbon Isotopes; D002552:Cerebral Ventricles; D004361:Drug Tolerance; D007267:Injections; D009020:Morphine / Q000008:administration & dosage / Q000134:cerebrospinal fluid / Q000494:pharmacology*; D010146:Pain; D011817:Rabbits; D012018:Reflex / Q000187:drug effects
chemical_list: D002247:Carbon Isotopes; D009020:Morphine