title: Morphine, oxycodone, and fentanyl exhibit different analgesic profiles in mouse pain models.
abstract: Morphine, oxycodone, and fentanyl are clinically prescribed drugs for the management of severe pain. We investigated whether these opioids possess different efficacy profiles on several types of pain in mouse pain models. When the three opioids were tested in the femur bone cancer model, all of them significantly reversed guarding behavior, whereas the effects on limb-use abnormality and allodynia-like behavior differed among the opioids. Particularly, although oxycodone (5 - 20 mg/kg) and fentanyl (0.2 mg/kg) significantly reversed limb-use abnormality, not even a high dose of morphine (50 mg/kg) could reverse it. When the effects of these opioids were examined in a sciatic nerve ligation (SNL) model of neuropathic pain, oxycodone was the most effective, producing an antinociceptive effect without affecting the withdrawal threshold of sham-treated animals. When the effects of these opioids were examined with the tail-flick test using naive animals, oxycodone, morphine, and fentanyl exhibited antinociceptive effects on thermal nociception. These results show that the three opioids exhibit different efficacy outcomes in multiple pain models and that the efficacy profile of oxycodone does not overlap those of morphine and fentanyl.
authors.affiliation: Pain & Neurology, Discovery Research Laboratories, Shionogi & Co., Ltd., Japan.
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Minami
authors.forename: Minoru
authors.initials: M
authors.lastname: Hasegawa
authors.forename: Hisanori
authors.initials: H
authors.lastname: Ito
authors.forename: Atsushi
authors.initials: A
authors.lastname: Nakamura
authors.forename: Takako
authors.initials: T
authors.lastname: Tomii
authors.forename: Mitsunobu
authors.initials: M
authors.lastname: Matsumoto
authors.forename: Satoshi
authors.initials: S
authors.lastname: Orita
authors.forename: Syuichi
authors.initials: S
authors.lastname: Matsushima
authors.forename: Takako
authors.initials: T
authors.lastname: Miyoshi
authors.forename: Koichi
authors.initials: K
authors.lastname: Masuno
authors.forename: Mikinori
authors.initials: M
authors.lastname: Torii
authors.forename: Katsumi
authors.initials: K
authors.lastname: Koike
authors.forename: Shinji
authors.initials: S
authors.lastname: Shimada
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Kanemasa
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Kihara
authors.forename: Minoru
authors.initials: M
authors.lastname: Narita
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Suzuki
authors.forename: Akira
authors.initials: A
authors.lastname: Kato
mesh_terms: D000700:Analgesics / Q000627:therapeutic use*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D004195:Disease Models, Animal; D005283:Fentanyl / Q000627:therapeutic use*; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008813:Mice, Inbred ICR; D009020:Morphine / Q000494:pharmacology / Q000627:therapeutic use*; D010098:Oxycodone / Q000627:therapeutic use*; D010146:Pain / Q000188:drug therapy*; D010147:Pain Measurement / Q000379:methods
chemical_list: D000700:Analgesics; D009020:Morphine; D010098:Oxycodone; D005283:Fentanyl