Recovery of endogenous analgesic function by antidepressants and its usefulness for persistent postoperative pain

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K16436
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 55050:Anesthesiology-related
• Research Institution: Gunma University
• Principal Investigator: Ohta Jo 群馬大学, 医学部附属病院, 助教 (30761100)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 神経障害性疼痛 / 術後痛 / ノルアドレナリン作動性神経系

Outline of Final Research Achievements

In rats with neuropathic pain in the chronic phase, the newly added plantar incision caused prolonged pain. The analgesic effects of the noradrenergic and muscarinic cholinergic nervous systems, which are important in the recovery process of normal postoperative pain, were lost in these animals. Continuous administration of the antidepressant amitriptyline for 5 days was able to restore the attenuated endogenous analgesic function in the medium term. Perioperative administration of amitriptyline for 13 consecutive days improved the prolongation of pain after plantar incision, but the mechanism significantly involved the muscarinic cholinergic nervous system rather than the noradrenergic nervous system.

Free Research Field

疼痛学

Academic Significance and Societal Importance of the Research Achievements

術後痛の正常な回復過程にはノルアドレナリン作動性神経系を含めた内因性鎮痛機能による鎮痛が作用している。慢性痛を抱えている場合には、内因性鎮痛機能機能が減弱化しているために、術後痛が遷延化する可能性がある。抗うつ薬アミトリプチリンには内因性鎮痛機能を賦活化させる作用があるため、抗うつ薬の周術期投与は術後痛の遷延化予防に役立つ可能性がある。