Characterization of methadone as a β-arrestin-biased κ-opioid receptor agonist. - Seira Doi; Tomohisa Mori; Naoki Uzawa; Takamichi Arima; Tomoyuki Takahashi; Masashi Uchida; Ayaka Yawata; Michiko Narita; Yasuhito Uezono; Tsutomu Suzuki; Minoru Narita (Molecular Pain, 2016)