title: ANALGESIC ACTION AND BRAIN AND PLASMA LEVELS OF MORPHINE AND CODEINE IN MORPHINE TOLERANT, CODEINE TOLERANT AND NON-TOLERANT RATS.
mesh_terms: D000700:Analgesics; D001769:Blood; D001921:Brain; D001923:Brain Chemistry; D003061:Codeine; D004361:Drug Tolerance; D009020:Morphine; D010600:Pharmacology; D051381:Rats; D012106:Research; D014116:Toxicology
chemical_list: D000700:Analgesics; D009020:Morphine; D003061:Codeine
keywords: BLOOD; BRAIN CHEMISTRY; CODEINE; DRUG TOLERANCE; EXPERIMENTAL LAB STUDY; MORPHINE; PHARMACOLOGY; RATS; TOXICOLOGIC REPORT