Aminopeptidase in human CSF which degrades delta-sleep inducing peptide (DSIP)

This study describes the purification and characterization of an aminopeptidase from human cerebrospinal fluid capable of degrading delta-sleep-inducing-peptide (DSIP). The enzyme has an apparent molecular weight of approximately 80,000 dalton. It is sensitive towards amastatin, bestatin and EDTA and is optimally active at neutral pH. The recovered enzyme was also found to degrade other neuropeptides, e.g., the enkephalins.