ET-1-INDUCED ATTENUATION OF MOR ACTIVITY DIFFERS BETWEEN MORPHINE AND FENTANYL. - Kaori Ohshima; Miki Nonaka; Yui Kuroda; Kanako Miyano; Hiroshi Takayanagi; Yasuhito Uezono (The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP), 2025)