Biomaterial Database

Multispecificity of Na+-dependent taurocholate uptake in basolateral (sinusoidal) rat liver plasma membrane vesicles. 1989

B Zimmerli, and J Valantinas, and P J Meier

Department of Medicine, University Hospital, Zurich, Switzerland.

To test the hypothesis of broad specificity of the hepatocellular bile acid uptake system(s) we investigated the kinetics and substrate specificity of Na+-dependent taurocholate uptake in basolateral (sinusoidal) rat liver plasma membrane vesicles in the presence and absence of bovine serum albumin. Bovine serum albumin selectively stimulated the Na+-dependent portion of taurocholate uptake and decreased its apparent Km from 46 +/- 6 to 17 +/- 3 microM, whereas it had no effect on Vmax (4.2 +/- 0.2 nmol.mg-1.min-1). Based on complementary analysis by Dixon- and Cornish-Bowden-plots the following compounds were identified as competitive inhibitors of Na+-dependent taurocholate uptake: cholate (Ki = 140 +/- 30 microM); taurochenodeoxycholate (Ki = 9 +/- 3 microM); chenodeoxycholate (Ki = 53 +/- 6 microM); progesterone (Ki = 110 +/- 30 microM); 17-beta-estradiol-3-sulfate (Ki = 28 +/- 4 microM); bumetanide (Ki = 440 +/- 85 microns); furosemide (Ki = 460 +/- 140 microM); verapamil (Ki = 65 +/- 35 microM); and phalloidin (Ki = 850 +/- 350 microM). In contrast, noncompetitive inhibition was found with bromosulfophthalein (Ki = 12 +/- 2 microM), cyclosporin A (Ki = 3 +/- 1 microM) and 4,4'-diisothiocyano-2,2'-disulfonic acid stilbene (Ki = 45 +/- 7 microM). These results support the concept of multispecificity of the Na+-dependent basolateral bile acid uptake system with respect to different bile acids and drugs. In addition, the findings provide further evidence for bile acids and bromosulfophthalein being taken up into rat hepatocytes by different transport systems, thus supporting the assumption of multiple basolateral organic anion "carriers" with distinct, yet partially overlapping substrate specificities.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008297	Male		Males
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000838	Anions	Negatively charged atoms, radicals or groups of atoms which travel to the anode or positive pole during electrolysis.	Anion
D001647	Bile Acids and Salts	Steroid acids and salts. The primary bile acids are derived from cholesterol in the liver and usually conjugated with glycine or taurine. The secondary bile acids are further modified by bacteria in the intestine. They play an important role in the digestion and absorption of fat. They have also been used pharmacologically, especially in the treatment of gallstones.	Bile Acid,Bile Salt,Bile Salts,Bile Acids,Acid, Bile,Acids, Bile,Salt, Bile,Salts, Bile
D001692	Biological Transport	The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.	Transport, Biological,Biologic Transport,Transport, Biologic
D012710	Serum Albumin, Bovine	Serum albumin from cows, commonly used in in vitro biological studies. (From Stedman, 25th ed)	Fetal Bovine Serum,Fetal Calf Serum,Albumin Bovine,Bovine Albumin,Bovine Serum Albumin,Albumin, Bovine,Albumin, Bovine Serum,Bovine Serum, Fetal,Bovine, Albumin,Calf Serum, Fetal,Serum, Fetal Bovine,Serum, Fetal Calf