Influence of some salicylates and sulfonamides on binding by albumin of SPC-703 and tolbutamide.
Bovine serum albumin has two different binding sites for sulfonylurea. The sites at high affinity can bind up to 2 moles of a new hypoglycemic sulfonylurea SPC-703 (k1=6.8.10(3) M(-1)) or tolbutamide K1=19.3.10(3) M(-1)). The sites of lower affinity can bind 4 mole of SPC-703 (K2=1.6.10(3) M(-1)) or 8 moles of tolbutamide (k2=1.3.10(3) M(-1)). Binding of SPC-703 and tolbutamide was decreased mostly in the presence of sulfadimetoxine, but this sulfonamide increased the concentration of free tolbutamide more than that of SPC-703.
D000818:Animals; D002417:Cattle; D003864:Depression, Chemical; D007004:Hypoglycemic Agents / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects; D011720:Pyrazoles / Q000378:metabolism; D012459:Salicylates / Q000494:pharmacology*; D012710:Serum Albumin, Bovine / Q000378:metabolism*; D013449:Sulfonamides / Q000494:pharmacology*; D013453:Sulfonylurea Compounds / Q000378:metabolism*; D014044:Tolbutamide / Q000378:metabolism*
D007004:Hypoglycemic Agents; D011720:Pyrazoles; D012459:Salicylates; D013449:Sulfonamides; D013453:Sulfonylurea Compounds; D012710:Serum Albumin, Bovine; D014044:Tolbutamide; C009971:glipalamide