Binedaline binding to plasma proteins and red blood cells in humans.
Serum binding of binedaline, a new antidepressant drug, was studied in vitro by equilibrium dialysis. The percent of binding in serum is high, 99.2%, and remains constant within the range of therapeutic concentrations; no saturation to the binding sites was seen. Investigations performed on isolated proteins with a wide range of concentrations showed one site with a high affinity constant (Ka = 2 X 10(6) M-1) for alpha 1-acid glycoprotein and two sites with a low affinity constant (Ka = 3 X 10(4) M-1) for human serum albumin. Binding to lipoproteins was nonsaturable, with a total affinity constant of 1.25 X 10(5) less than nKa less than 2.79 X 10(6) M-1. Over the range of therapeutic concentrations, the ratio of binedaline concentrations in serum and red blood cells remained constant (1%) and was shown to be dependent on the free fraction of binedaline in serum.
D000928:Antidepressive Agents / Q000097:blood*; D001798:Blood Proteins / Q000378:metabolism*; D003956:Dialysis; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007211:Indoles / Q000097:blood*; D007700:Kinetics; D008074:Lipoproteins / Q000378:metabolism; D009961:Orosomucoid / Q000378:metabolism; D011485:Protein Binding; D012709:Serum Albumin / Q000378:metabolism
D000928:Antidepressive Agents; D001798:Blood Proteins; D007211:Indoles; D008074:Lipoproteins; D009961:Orosomucoid; D012709:Serum Albumin; C044680:binedaline