Specific binding of human corticosteroid-binding globulin to cell membranes.
Specific binding sites for corticosteroid-binding globulin were detected on membranes prepared from human prostates. The binding sites are typical of membrane receptors: they are saturable and specific and have high affinity. There was little specific binding at 4 degrees C and 23 degrees C. Maximal specific binding was obtained at 37 degrees C. Scatchard analysis revealed the presence of a single set of binding sites with an apparent dissociation constant of 8.7 X 10(-7) M and a binding capacity of 22 pmol/mg of membrane protein. The sites were specific for corticosteroid-binding globulin; binding was not inhibited by human testosterone/estradiol-binding globulin, by albumin, or by transferrin. The density of specific binding sites in membranes obtained from several organs from the rhesus monkey is consistent with the hypothesis that corticosteroid-binding globulin is involved in the transport of steroid hormones into target tissues.
D000418:Albumins / Q000378:metabolism; D000818:Animals; D001692:Biological Transport; D002462:Cell Membrane / Q000378:metabolism*; D005260:Female; D006801:Humans; D007700:Kinetics; D008253:Macaca mulatta; D008297:Male; D011467:Prostate / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D013696:Temperature; D014018:Tissue Distribution; D014156:Transcortin / Q000378:metabolism*; D014168:Transferrin / Q000378:metabolism
D000418:Albumins; D011956:Receptors, Cell Surface; D012738:Sex Hormone-Binding Globulin; D014168:Transferrin; D014156:Transcortin