ABSTRACT
The comparative study of the ability of three compounds (indomethacin, agent BW 755 C and arachidonate hydroxamic acid) to inhibit the activity of preparations of soya bean lipoxygenase and to block leukotriene C4 biosynthesis in human leukocytes recorded by reversed phase liquid chromatography was performed. It was shown that irrespectively of purification degree soya bean lipoxygenase is a sufficiently adequate object for primary testing of inhibitors of biosynthesis of leukotrienes with the given type of action. Compounds with IC50 less than or equal to 1.10(-6) mol/l might be considered promising for the further investigation.
Subject(s)
Arachidonate Lipoxygenases/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Glycine max/enzymology , Lipoxygenase Inhibitors , SRS-A/antagonists & inhibitors , 4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyrazol-3-amine , Arachidonic Acids/pharmacology , Calcimycin/pharmacology , Chromatography, High Pressure Liquid , Drug Evaluation, Preclinical , Humans , Hydroxamic Acids/pharmacology , Indomethacin/pharmacology , Leukocytes/drug effects , Leukocytes/metabolism , Lymphocyte Activation/drug effects , Pyrazoles/pharmacology , SRS-A/analysis , Spectrophotometry, UltravioletABSTRACT
NADH has a corresponding binding site in aldolase, and can activate the reaction of the aldole cleavage of the substrate (fructose-1,6-bisphosphate). Unlike the considerable protection by the substrate, the similar effect of NADH on the sulphydryl enzyme groups is less pronounced, and may be attributed to single cysteine residue. The functionally related and spatially separated binding sites for NADH and substrate are suggested.
Subject(s)
Fructose-Bisphosphate Aldolase/metabolism , Muscles/enzymology , NAD/pharmacology , Sulfhydryl Compounds/metabolism , Animals , Binding Sites , Catalysis , In Vitro Techniques , Muscles/metabolism , NAD/metabolism , Protein Conformation , Rabbits , Substrate SpecificityABSTRACT
This simple and easily reproducible technique does not pretend to be new in principle but is still very convenient for drying numerous samples. The advantage of the technique is based on preliminary sample freezing just before dessication. The tubes must be sealed with needle punctured cellophane to avoid the samples squeezing out by ice-entraped air bubbles. This approach is especially convenient for protein structure investigations when it is necessary to dry and accumulate peptides from the maps on high-voltage electrophoresis and chromatography. In a 1.5-litre dessicator some 20 ml of sample can be dried out without reloading.