caa a22 4500 378879235 CHVBK 20180305123428.0 cr unu---uuuuu 161128e20030721xx s 000 0 eng 10.1515/CCLM.2003.138 doi (NATIONALLICENCE)gruyter-10.1515/CCLM.2003.138 Fluorometric Assays of Phospholipase A2 Activity with Three Different Substrates in BiologicalSamples of Patients with Schizophrenia [Elektronische Daten] [Jürgen Lasch, Ingo Willhardt, Daniel Kinder, Heinrich Sauer, Stefan Smesny] The rationale of this study was to understand the complexity of kinetics of fluorogenic phospholipid substratesas well as contradictory findings of clinical papers measuring phospholipase A2 (PLA2) activity using different methodologies. The aim was to recommend to clinicians and researchers what substrate in conjunction with what assay should be used. Two methods, (i) continuous fluorometric assay and (ii) high performance thin layer chromatography (HPTLC) on microplates combined with quantitative image scanning, were studied with three different substrates (bis-BODIPY® FL C11-PC, NBDC6-HPC®, PED6®). The study demonstrates that NBD-PC is not a suitable substrate to measure PLA2 activity using a spectrofluorometer. On the other hand, NBD-PC gives the highest and most reproducible integrated light intensities (ILIs) in HPTLC studies. Slow time-dependent increases in fluorescence intensities recorded with biological samples in fluorometers, but not caused by substrate splitting, had to be classified as "perturbation kinetics”. PLA2 activities in blood samples of 26 unmedicated schizophrenia patients and 26 age-matched healthy controls were measured by the spectrofluorometric method and then compared with the activity data obtained with the HPTLC method. A significant group difference was found only with the HPTLC. In order to get more reliable results, we recommend that clinicians and researchers use NBD-phosphatidylcholines as PLA2 substrates in biological samples and start with an analytical separation of reaction products followed by image analysis of the fluorescent spots. Copyright © 2003 by Walter de Gruyter GmbH & Co. KG Medical equipment & techniques nationallicence Medical diagnosis nationallicence Diseases & disorders nationallicence Lasch Jürgen aut Willhardt Ingo aut Kinder Daniel aut Sauer Heinrich aut Smesny Stefan aut Clinical Chemistry and Laboratory Medicine Walter de Gruyter 41/7(2003-07-21), 908-914 1434-6621 41:7<908 2003 41 cclm https://doi.org/10.1515/CCLM.2003.138 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.1515/CCLM.2003.138 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lasch Jürgen aut NATIONALLICENCE 700 1- Willhardt Ingo aut NATIONALLICENCE 700 1- Kinder Daniel aut NATIONALLICENCE 700 1- Sauer Heinrich aut NATIONALLICENCE 700 1- Smesny Stefan aut NATIONALLICENCE 773 0- Clinical Chemistry and Laboratory Medicine Walter de Gruyter 41/7(2003-07-21), 908-914 1434-6621 41:7<908 2003 41 cclm CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter