Biomaterial Database

Transport of spin-labeled tetracycline across model and biological membranes. 1993

A Pezeshk, and V Pezeshk, and A Firlej, and J Wojas, and W K Subczynski

Department of Chemistry, Moorhead State University, Minnesota 56563.

Electron spin resonance spectra of spin labeled tetracycline (TC-SL) do not show any recognizable partitioning into a lipid bilayer or bulk hydrocarbon solvent, paraffin oil. TC-SL, however, penetrates through the model and biological membranes. It is shown that the rate of permeation depends on membrane composition and increases with temperature. In fluid phase, the rate is greater for saturated dimyristoylphosphatidylcholine than for unsaturated egg yolk phosphatidylcholine membranes. Cholesterol significantly decreases the rate, 30 mol% cholesterol decreases the rate of TC-SL permeation across egg yolk phosphatidylcholine bilayer 8 times at 37 degrees C. The rate of permeation of TC-SL across model membranes is much smaller than the rate for TEMPONE--a compound which slightly partitions into lipid bilayer, and much greater than the rate for TEMPO--choline-a positively charged compound. After addition to the suspension of Ehrlich's ascites tumor cells, the TC-SL is reduced to a non-paramagnetic form. Reduction rate is independent of oxygen concentrations, which led us to suggest that the permeation of TC-SL across the cell plasma membrane is the limiting step of reduction reaction.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008081	Liposomes	Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.	Niosomes,Transferosomes,Ultradeformable Liposomes,Liposomes, Ultra-deformable,Liposome,Liposome, Ultra-deformable,Liposome, Ultradeformable,Liposomes, Ultra deformable,Liposomes, Ultradeformable,Niosome,Transferosome,Ultra-deformable Liposome,Ultra-deformable Liposomes,Ultradeformable Liposome
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D010539	Permeability	Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.	Permeabilities
D002286	Carcinoma, Ehrlich Tumor	A transplantable, poorly differentiated malignant tumor which appeared originally as a spontaneous breast carcinoma in a mouse. It grows in both solid and ascitic forms.	Ehrlich Ascites Tumor,Ascites Tumor, Ehrlich,Ehrlich Tumor Carcinoma,Tumor, Ehrlich Ascites
D004578	Electron Spin Resonance Spectroscopy	A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.	ENDOR,Electron Nuclear Double Resonance,Electron Paramagnetic Resonance,Paramagnetic Resonance,Electron Spin Resonance,Paramagnetic Resonance, Electron,Resonance, Electron Paramagnetic,Resonance, Electron Spin,Resonance, Paramagnetic
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
D013113	Spin Labels	Molecules which contain an atom or a group of atoms exhibiting an unpaired electron spin that can be detected by electron spin resonance spectroscopy and can be bonded to another molecule. (McGraw-Hill Dictionary of Chemical and Technical Terms, 4th ed)	Spin Label,Label, Spin,Labels, Spin
D013752	Tetracycline	A naphthacene antibiotic that inhibits AMINO ACYL TRNA binding during protein synthesis.	4-Epitetracycline,Achromycin,Achromycin V,Hostacyclin,Sustamycin,Tetrabid,Tetracycline Hydrochloride,Tetracycline Monohydrochloride,Topicycline,4 Epitetracycline
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus