Combining solid-phase preconcentration, capillary electrophoresis and off-line matrix-assisted laser desorption/ionization mass spectrometry: Intracerebral metabolic processing of peptide E in vivo

The in vivo metabolism of peptide E was studied in the anesthetized rat usi ng a combination of microdialysis sampling, solid-phase preconcentration ca pillary electrophoresis and imaging matrix-assisted laser desorption/ioniza tion mass spectrometry (MALDI/MS). The metabolic profile of peptides identi fied by MALDI/MS showed that the primary enzymatic activity for degradation of peptide E was due to carboxypeptidases and, to a lesser extent, aminope ptidases and some trypsin-like endopeptidases. Over 75 metabolic fragments were detected from the action of these enzymes in vivo, Copyright (C) 1999 John Wiley & Sons Ltd.