[Fluorescent method of determining serotonin deaminating monoamine oxidase activity based on the amount of 5-hydroxyindoleacetic acid].
A fluorimetric procedure is developed for estimation of serotonin deaminating activity of MAO by measuring the oxidized reaction product-5-hydroxyindolyl acetic acid (5-HIAA) extracted from acid solution by means of diethyl ester with subsequent transfer in 0.1 M phosphate buffer, pH 7.3. The optimal conditions for the extraction were developed, ensuring the maximal yield of 5-HIAA and serotonin. Low content of serotonin was found in the phosphate buffer. The concentration of serotonin was similar both in test and control samples; it did not interfere with the estimation of 5-HIAA. Sensitivity and reproducibility of 5-HIAA estimation by means of its fluorescence in 3 N HCI was higher as compared with the reaction with o-phthalic dialdehyde. Yield of 5-HIAA extracted from solution was approximately 90%. Activity of MAO, as shown by reaction of 5-HIAA with o-phthalic dialdehyde, was equal to 2.81 +/- 0.19 nM/mg/min (n = 15) and - by fluorescence in 3 N HCL - 2.92 +/- 0.29 nM/mg/min (n = 12).
D000818:Animals; D001921:Brain / Q000201:enzymology; D002417:Cattle; D003641:Deamination; D005456:Fluorescent Dyes / Q000032:analysis; D006897:Hydroxyindoleacetic Acid / Q000032:analysis*; D008928:Mitochondria / Q000201:enzymology; D008995:Monoamine Oxidase / Q000032:analysis*; D010084:Oxidation-Reduction; D051381:Rats; D012701:Serotonin / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
D005456:Fluorescent Dyes; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D008995:Monoamine Oxidase
Fluorestsentnyĭ metod opredeleniia serotonindezaminiruiushcheĭ aktivnosti monoaminoksidazy po kolichestvu 5-oksiindoluksusnoĭ kisloty.