“…Modelling structures of complexes formed by KOP and its agonists or antagonists has been attempted for more than 20 years (Alonso, Bliznyuk, & Gready, 2006;Bailey & Husbands, 2018;Benyhe, Zador, & Otvos, 2015;Bera, Marathe, Payghan, & Ghoshal, 2018;Gentilucci, Tolomelli, De Marco, & Artali, 2012;Johnson, 2017;Kane, Svensson, & Ferguson, 2006;Kaserer, Lantero, Schmidhammer, Spetea, & Schuster, 2016;Kolinski & Filipek, 2010;Lavecchia, Greco, Novellino, Vittorio, & Ronsisvalle, 2000;Martinez-Mayorga et al, 2013;Patra, Kumar, Pasha, & Chopra, 2012;Tessmer, Meyer, Hruby, & Kallick, 1997;Wu, Song, Graaf, & Stevens, 2017;Yongye & Martínez-Mayorga, 2012). Some of these models specifically focused on dynorphin (Bjorneras, et al, 2014;Charles Chavkin, 2013;Iadanza, Höltje, Ronsisvalle, & Höltje, 2002;Kang, et al, 2015;O'Connor, et al, 2015;Paterlini, Portoghese, & Ferguson, 1997;Sankararamakrishnan & Weinstein, 2000;Smeets et al, 2016;Vardy, et al, 2013). Early studies, performed before any experimentally determined receptor structures were available, were based entirely on modelling (Iadanza, et al, 2002;Paterlini, et al, 1997;Wan et al, 2000).…”