Characterization of Membrane‐Bound Aminopeptidases from Rat Brain: Identification of the Enkephalin‐Degrading Aminopeptidase

Louis B. Hersh

Research output: Contribution to journalArticlepeer-review

78 Scopus citations

Abstract

Abstract: Rat brain aminopeptidase activity was solubilized from membranes by incubation with thiols. This novel procedure resulted in the release of the same two aminopeptidases (MI and MII) previously shown to be solubilized by the nonionic detergent Triton X‐100. The solubilized aminopeptidases MI and MII were resolved by ion‐exchange chromatography and further purified by hydroxylapatite chromatography. Aminopeptidase MI was shown to hydrolyze only the β‐naphthylamides of arginine and lysine whereas aminopeptidase MII exhibited a broad specificity with respect to amino acid β‐naphthylamides. Only aminopeptidase MII hydrolyzed Leu‐enkephalin at a significant rate, indicating that this enzyme can account for the membrane‐bound enkephalin aminopeptidase activity. The enkephalin‐degrading aminopeptidase is potently inhibited by opioid (α‐neo‐endorphin and dynorphin) as well as nonopioid (substance P, somatostatin, and angiotensin I) peptides in the range of 0.2–2.0 μM The regional distribution of aminopeptidases MI and MII in rat brain are rather different, with aminopeptidase MII distribution more closely paralleling the distribution of opiate receptors.

Original languageEnglish
Pages (from-to)1427-1435
Number of pages9
JournalJournal of Neurochemistry
Volume44
Issue number5
DOIs
StatePublished - May 1985

Keywords

  • Aminopeptidases
  • Enkephalin degradation

ASJC Scopus subject areas

  • Biochemistry
  • Cellular and Molecular Neuroscience

Fingerprint

Dive into the research topics of 'Characterization of Membrane‐Bound Aminopeptidases from Rat Brain: Identification of the Enkephalin‐Degrading Aminopeptidase'. Together they form a unique fingerprint.

Cite this