Identification of the role of spino-parabrachio-amygdaloid pathway in the pain-associated emotion

2016 Fiscal Year Final Research Report

• Project/Area Number: 25293136
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Pain science
• Research Institution: Jikei University School of Medicine
• Principal Investigator: Kato Fusao 東京慈恵会医科大学, 医学部, 教授 (20169519)
• Co-Investigator(Renkei-kenkyūsha): Watabe M Ayako 東京慈恵会医科大学, 医学部, 教授 (00334277) ; Takahashi Yukari 東京慈恵会医科大学, 医学部, 助教 (20613764)
• Project Period (FY): 2013-04-01 – 2017-03-31
• Keywords: 扁桃体 / 腕傍核 / 慢性痛 / 恐怖・脅威学習 / 情動 / 光遺伝学 / 化学遺伝学 / 痛み

Outline of Final Research Achievements

To clarify the mechanism underlying the link between pain and negative emotion (suffering), we focused on the spino-parabrachio-amygdaloid pathway: 1) Optogenetic activation of the parabrachial-central amygdala pathway alone functions as unconditioned stimulus in Pavlovian and operant conditional learning. 2) This evoked mono- and polysynaptic network-driven activities in the central amygdala neurons, which was potentiated in the persistent inflammatory pain model. And 3) chemogenetic inhibition of GABAergic neurons in the central amygdala in the inflammatory pain model mitigated hypersensitivity and chemogenetic activation of these gave rise to the hypersensitivity in normal rats. These results indicate that this pathway is the primary route for the aversive nociceptive information to activate the limbic system leading to not only the negative emotion but also the elevated sensitivity to potentially harmful events.

Free Research Field

神経生理学・疼痛学