ABSTRACT
Benzopyrylium dye BDBP was found to be an effective uncoupler of oxidative phosphorylation. It stimulates state 4 respiration of mitochondria 2-fold at about 2 microM, reveals a maximum stimulation (8-fold) at 30 microM and inhibits the respiration at higher concentrations. BDBP is also an effective proton (hydroxyl) carrier through bilayer lipid membranes (BLM) as is seen from the electrical properties of BLM with BDBP. Picrate enhances the effects of BDBP on the mitochondrial respiration and BLM conductance. The BDBP activities are accounted for by formation of dimers and complexes with picrate.
Subject(s)
Benzopyrans/pharmacology , Coloring Agents/chemistry , Oxidative Phosphorylation , Uncoupling Agents , Animals , Cattle , Kinetics , Lipid Bilayers , Male , Mitochondria/metabolism , Molecular Structure , Rats , Rats, WistarABSTRACT
In the experiments with artificial lipid membranes and mitochondria the watersoluble pea flavonols are demonstrated to possess weak protonophoric and uncoupling activities which correlate with each other. It is concluded that the mechanism of flavonol uncoupling activity is the same as for classical uncouplers. The results support the earlier suggestion that one of the flavonol functions in the plants may be the regulation of the energetics and metabolism.
Subject(s)
Fabaceae/analysis , Flavonoids , Ionophores , Plants, Medicinal , Uncoupling Agents , Animals , Flavonoids/isolation & purification , Flavonoids/pharmacology , In Vitro Techniques , Membranes, Artificial , Mitochondria, Liver/drug effects , Protons , RatsABSTRACT
The effects of compounds (see article), where M = -S-, -SO-, -SO2- and of some of their derivatives (18 substances) on electroconductivity of bimolecular lipid membranes (BLM) of different composition in 30 mM tris-HCl (pH 7.5) is studied. The results obtained are compared with literature data concerning fasciolocide and toxic effect of these substances. Certain correlations are found between the action on BLM and biological effects of substances. The analysis of the results allowed a conclusion that the latter are concerned with a discoupling effect of substances on oxidative phosphorylation in mitochondria of helmets and their host. BLM may be applied for evaluating the value of fasciolocide and toxic effects of the substances protonophores.
