EVALUATION OF EXTRACELLULAR LIPID-PEROXIDATION IN BRAIN CORTEX OF ANESTHETIZED RATS BY MICRODIALYSIS PERFUSION AND HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH FLUOROMETRIC DETECTION

A method for in vivo evaluation of lipid peroxidation in the extracell ular space of anaesthetized rat brain cortex was developed, This metho d involved the use of microdialysis perfusion and high-performance liq uid chromatography, The microdialysates, eluted from implanted probes, were reacted with thiobarbituric acid (TBA) prior to analysis by an H PLC system equipped with a fluorescence detector (excitation and emiss ion wavelengths were 515 and 550 nm, respectively), Lipid peroxidation in the extracellular space was evaluated as the concentration of malo ndialdehyde, a lipid peroxidation end product which reacts with TBA to form a fluorescent conjugate, Significantly increased production of m alondialdehyde following hydrogen peroxide perfusion (0.03%, 0.3% at a flow-rate of 1 mu l/min) was observed in the brain cortex of anaesthe tized rats.