Biomaterial Database

Binding of diazepam and desmethyldiazepam to plasma protein: concentration-dependence and interactions. 1981

M Divoll, and D J Greenblatt

The binding of diazepam (DZ) and its major metabolite desmethyldiazepam (DMDZ) to plasma protein was evaluated in a series of controlled in vitro studies using equilibrium dialysis. Free fraction (FF) of both drugs alone changed significantly with total plasma drug concentration, but the increased FF (reduction in binding) did not occur until concentrations considerably exceeded those encountered during typical therapeutic use. Increasing concentrations of one drug at a time tended to increase FF for the other, although the effects were, at most, of borderline significance. Simultaneously increasing concentrations of both drugs led to significantly increased FF for both. Thus, DZ and DMDZ appear to bind to the same site or sites on plasma albumin. Binding is concentration-independent within and considerably above the usual therapeutic range.

UI	MeSH Term	Description	Entries
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D001798	Blood Proteins	Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.	Blood Protein,Plasma Protein,Plasma Proteins,Serum Protein,Serum Proteins,Protein, Blood,Protein, Plasma,Protein, Serum,Proteins, Blood,Proteins, Plasma,Proteins, Serum
D003708	Nordazepam	An intermediate in the metabolism of DIAZEPAM to OXAZEPAM. It may have actions similar to those of diazepam.	Dealkylprazepam,Demethyldiazepam,Deoxydemoxepam,Desmethyldiazepam,Nordiazepam,Calmday,N-Desalkylhalazepam,N-Descyclopropylmethyl-Prazepam,N-Descyclopropylmethylprazepam,N-Destrifluoroethylhalazepam,Nordaz,Norprazepam,Ro 5-2180,Tranxilium N,Vegesan,N Desalkylhalazepam,N Descyclopropylmethyl Prazepam,N Descyclopropylmethylprazepam,N Destrifluoroethylhalazepam,Ro 5 2180,Ro 52180
D003956	Dialysis	A process of selective diffusion through a membrane. It is usually used to separate low-molecular-weight solutes which diffuse through the membrane from the colloidal and high-molecular-weight solutes which do not. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Dialyses
D003975	Diazepam	A benzodiazepine with anticonvulsant, anxiolytic, sedative, muscle relaxant, and amnesic properties and a long duration of action. Its actions are mediated by enhancement of GAMMA-AMINOBUTYRIC ACID activity.	7-Chloro-1,3-dihydro-1-methyl-5-phenyl-2H-1,4-benzodiazepin-2-one,Apaurin,Diazemuls,Faustan,Relanium,Seduxen,Sibazon,Stesolid,Valium
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001667	Binding, Competitive	The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.	Competitive Binding
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In