Three peptide neuromodulators that are found in high concentration in the subtantia nigra: dynorphin A 1-8, met5-enkephalin-arg6-gly7-leu8 and substance P, were measured by specific radioimmunoassays in nigral tissue from normals and schizophrenics postmortem. Substance P and dynorphin were unchanged between the two groups. However, the proenkephalin-derived peptide was significantly elevated in the schizophrenic group. The immunoreactivity was identified as authentic met5-enkephalin-arg6-gly7-leu8 by high pressure liquid chromatography. The data suggest that a different set of regulatory controls exists for nigral enkephalin peptides as compared to dynorphin and substance P, and that the former system may be disordered in schizophrenia.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Pharmacology, Toxicology and Pharmaceutics(all)