Biomaterial Database

Differential theophylline inhibition of alkaline phosphatase and 5'-nucleotidase of bovine milk fat globule membranes. 1991

X Dai, and L D Snow

Department of Chemistry, Louisiana Tech University, Ruston, LA 71272.

1. The effects of theophylline (1,3-dimethylxanthine) on alkaline phosphatase and 5'-nucleotidase activities of bovine milk fat globule membranes (MFGM) were examined. 2. Theophylline inhibited MFGM alkaline phosphatase in a concentration-dependent manner with 50% inhibition produced by 99 +/- 28 microM theophylline. 3. The 5'-nucleotidase activity was resistant to theophylline inhibition with 50% inhibition produced by 33.9 +/- 3.1 mM theophylline. 4. Theophylline was an uncompetitive inhibitor of MFGM alkaline phosphatase with a Ki of 126 +/- 15 microM. 5. The extent of theophylline inhibition of alkaline phosphatase activity was independent of the substrate utilized in the assay. 6. The effect of theophylline on bovine MFGM alkaline phosphatase was similar to theophylline effects on other mammalian alkaline phosphatases of liver/bone isoenzyme origin.

UI	MeSH Term	Description	Entries
D007291	Inosine Monophosphate	Inosine 5'-Monophosphate. A purine nucleotide which has hypoxanthine as the base and one phosphate group esterified to the sugar moiety.	IMP,Inosinic Acid,Ribosylhypoxanthine Monophosphate,Inosinic Acids,Sodium Inosinate,Acid, Inosinic,Acids, Inosinic,Inosinate, Sodium,Monophosphate, Inosine,Monophosphate, Ribosylhypoxanthine
D007527	Isoenzymes	Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.	Alloenzyme,Allozyme,Isoenzyme,Isozyme,Isozymes,Alloenzymes,Allozymes
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008055	Lipids	A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)	Lipid
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
D008321	Mammary Glands, Animal	MAMMARY GLANDS in the non-human MAMMALS.	Mammae,Udder,Animal Mammary Glands,Animal Mammary Gland,Mammary Gland, Animal,Udders
D008892	Milk	The off-white liquid secreted by the mammary glands of humans and other mammals. It contains proteins, sugar, lipids, vitamins, and minerals.	Cow Milk,Cow's Milk,Milk, Cow,Milk, Cow's
D009596	Nitrophenols	PHENOLS carrying nitro group substituents.	Nitrophenol
D009943	Organophosphorus Compounds	Organic compounds that contain phosphorus as an integral part of the molecule. Included under this heading is broad array of synthetic compounds that are used as PESTICIDES and DRUGS.	Organophosphorus Compound,Organopyrophosphorus Compound,Organopyrophosphorus Compounds,Compound, Organophosphorus,Compound, Organopyrophosphorus,Compounds, Organophosphorus,Compounds, Organopyrophosphorus
D001842	Bone and Bones	A specialized CONNECTIVE TISSUE that is the main constituent of the SKELETON. The principal cellular component of bone is comprised of OSTEOBLASTS; OSTEOCYTES; and OSTEOCLASTS, while FIBRILLAR COLLAGENS and hydroxyapatite crystals form the BONE MATRIX.	Bone Tissue,Bone and Bone,Bone,Bones,Bones and Bone,Bones and Bone Tissue,Bony Apophyses,Bony Apophysis,Condyle,Apophyses, Bony,Apophysis, Bony,Bone Tissues,Condyles,Tissue, Bone,Tissues, Bone