RAPID AND SIMPLE METHOD FOR THE DETERMINATION OF PICOGRAM LEVELS OF SEROTONIN IN BRAIN-TISSUE USING LIQUID-CHROMATOGRAPHY WITH ELECTROCHEMICAL DETECTION

A rapid and simple technique using solvent extraction and high pressure liquid chromatography with electrochemical detection has been developed for the determination of serotonin in small brain tissue samples (1‐20 mg). The method has a reasonably good specificity and a very low experimental error (less than 3%s.e., calculated from six samples processed and analysed from the same brain homogenate). The recovery of authentic 5‐HT added is 80‐90%. The 5‐HT levels of rat whole brain was found with the present technique to be 690 ± 17.5 ng/g and of mouse neocortex 304 ± 16 ng/g. Monoamine oxidase inhibition with pargyline (2 h) increased 5‐HT levels in mouse neocortex to 194 ± 15% (N = 5) of control, while reserpine depleted 5‐HT to 13 ± 4% of control. The method has a sensitivity level of about 20 pg (0.1 pmol) per brain sample. Copyright © 1979, Wiley Blackwell. All rights reserved