Biomaterial Database

Effect of microcystin-LR (MCLR) on hepatic microsomal membrane fluidity. 1991

S J Hermansky, and S J Stohs

Department of Pharmaceutical Sciences, School of Pharmacy and Allied Health Professions, Creighton University, Omaha, NE 68178.

Microcystin-LR (MCLR) is a potent cyclic heptapeptide hepatotoxin which appears to cause death due to hemorrhagic shock secondary to blood loss from the vasculature into the damaged liver. The molecular mechanism of toxicity is not known. Previous studies have demonstrated altered hepatic sulfhydryl status and enhanced lipid peroxidation following exposure of mice to MCLR. In the present study, mice were treated with 100 micrograms MCLR/kg and killed 10, 20 or 30 min post-treatment. Significant time-dependent decreases in hepatic microsomal membrane fluidity occurred. When microsomes from control animals were incubated in vitro with various concentrations of MCLR, no alterations in membrane fluidity were observed. The results suggest that MCLR-induced alterations in microsomal membrane fluidity involve an indirect and secondary effect rather than a direct interaction of the toxin with the membranes.

UI	MeSH Term	Description	Entries
D008051	Lipid Bilayers	Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.	Bilayers, Lipid,Bilayer, Lipid,Lipid Bilayer
D008387	Marine Toxins	Toxic or poisonous substances elaborated by marine flora or fauna. They include also specific, characterized poisons or toxins for which there is no more specific heading, like those from poisonous FISHES.	Marine Biotoxins,Phycotoxins
D008560	Membrane Fluidity	The motion of phospholipid molecules within the lipid bilayer, dependent on the classes of phospholipids present, their fatty acid composition and degree of unsaturation of the acyl chains, the cholesterol concentration, and temperature.	Bilayer Fluidity,Bilayer Fluidities,Fluidities, Bilayer,Fluidities, Membrane,Fluidity, Bilayer,Fluidity, Membrane,Membrane Fluidities
D008862	Microsomes, Liver	Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.	Liver Microsomes,Liver Microsome,Microsome, Liver
D010456	Peptides, Cyclic	Peptides whose amino acid residues are linked together forming a circular chain. Some of them are ANTI-INFECTIVE AGENTS; some are biosynthesized non-ribosomally (PEPTIDE BIOSYNTHESIS, NON-RIBOSOMAL).	Circular Peptide,Cyclic Peptide,Cyclic Peptides,Cyclopeptide,Orbitide,Circular Peptides,Cyclopeptides,Orbitides,Peptide, Circular,Peptide, Cyclic,Peptides, Circular
D005260	Female		Females
D005454	Fluorescence Polarization	Measurement of the polarization of fluorescent light from solutions or microscopic specimens. It is used to provide information concerning molecular size, shape, and conformation, molecular anisotropy, electronic energy transfer, molecular interaction, including dye and coenzyme binding, and the antigen-antibody reaction.	Anisotropy, Fluorescence,Fluorescence Anisotropy,Polarization, Fluorescence,Anisotropies, Fluorescence,Fluorescence Anisotropies,Fluorescence Polarizations,Polarizations, Fluorescence
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
D015227	Lipid Peroxidation	Peroxidase catalyzed oxidation of lipids using hydrogen peroxide as an electron acceptor.	Lipid Peroxidations,Peroxidation, Lipid,Peroxidations, Lipid
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