Kappa binding model

Paterlini G, Portoghese P, Ferguson D. Molecular simulation of dynorphin A-(1—10) binding to extracellular loop 2 of the kappa opioid receptor. A model for receptor activation. J Med Chem 1997 40 3254-3262. 

Several opiate receptors have been identified on cells of the nervous systems of animals and humans, with mu (p), kappa (k), and gamma (y) subtypes being predominant. These classical opiate receptors are G- protein coupled 7-transmembrane molecules.27 Opiates predominantly affect immune responses directly by ligation of p, k, and y opiate receptors, as well as non-classical opiate-like receptors, on immune cells and indirectly by binding to receptors on CNS cells. Studies conducted in vitro with opiate-treated immune cells demonstrated receptor-mediated reduced phagocytosis, chemotaxis and cytokine and chemokine production. These effects are linked to modulation of host resistance to bacterial, protozoan, viral and fungal infections using animal models, cell lines and primary cells. 

Kane BE, Nieto MJ, McCurdy CR, Ferguson DM (2006) A unique binding epitope for salvinorin A, a non-nitrogenous kappa opioid receptor agonist. FEBS J 273 1966-1974 Kane BE, McCurdy CR, Ferguson DM (2008) Toward a structure-based model of salvinorin A recognition of the K-opioid receptor. J Med Chem 51 1824-1830... 

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