Are released and concentrated in the substantia gelatinosa and bind to specific receptors.

journal article

Scientific American

Vol. 236, No. 3 (March 1977)

, pp. 44-57 (14 pages)

Published By: Scientific American, a division of Nature America, Inc.

https://www.jstor.org/stable/24953936

Read and download

Log in through your school or library

Journal Information

Scientific American is the authority on science and technology for a general audience, with coverage that explains how research changes our understanding of the world and shapes our lives. First published in 1845, Scientific American is the longest continuously published magazine in the US. The magazine has published articles by more than 150 Nobel Prize-winning scientists and built a loyal following of influential and forward thinking readers. The archives of Scientific American include articles penned by Albert Einstein, Thomas Edison, Jonas Salk, Marie Curie, Stephen Hawking, Franklin D. Roosevelt, Stephen Jay Gould, Bill Gates, and more.

Publisher Information

Founded in 1845, Scientific American is the oldest continuously published magazine in the US and the leading authoritative publication for science and technology in the general media. Scientific American is published by Springer Nature, a leading global research, educational and professional publisher, home to an array of respected and trusted brands providing quality content through a range of innovative products and services. Springer Nature was formed in 2015 through the merger of Nature Publishing Group, Palgrave Macmillan, Macmillan Education and Springer Science+Business Media.

Abstract

The neutral endopeptidase EC 3.4.24.11, also designated enkephalinase, has been visualized by in vitro autoradiography using the tritiated inhibitor [3H]-N-[(2RS)-3-hydroxyaminocarbonyl-2-benzyl-1-oxoprop yl]glycine, ([3H]HACBO-Gly). Specific binding of [3H]HACBO-Gly (Kd = 0.4 ± 0.05 nM) corresponding to 85% of the total binding to brain slices was inhibited by 1 μ M thiorphan, a selective inhibitor of enkephalinase, but remained unchanged in the presence of captopril, a selective inhibitor of angiotensin-converting enzyme. Very high levels of [3H]HACBO-Gly binding were found in the choroid plexus and the substantia nigra. High levels were present in the caudate putamen, globus pallidus, nucleus accumbens, olfactory tubercle, and in the substantia gelatinosa of the spinal cord. Moderate densities were found in parts of the amygdala, the periaqueductal gray matter, the interpeduncular nucleus, and the molecular layer of the cerebellum. The distribution of enkephalinase was compared to that of μ and δ opioid receptors, selectively labeled with [3H]Tyr-D-Ala-Gly-MePhe-glycinol and [3H]Tyr-D-Thr-Gly-Phe-Leu-Thr, respectively. In the caudate putamen, [3H]HACBO-Gly binding overlapped the clustered μ sites but appeared more closely related to the diffusely distributed δ sites. High levels of enkephalinase and μ opioid binding sites were present at the level of the periaqueductal gray matter and in the substantia gelatinosa of the spinal cord, regions where only sparse δ opioid receptors could be detected. The association of enkephalinase with δ and μ opioid receptors in these areas in consistent with the observed role of the enzyme in regulating the effects of opioid peptides in striatal dopamine release and analgesia, respectively. Except for the choroid plexus and the cerebellum, the close similarity observed in numerous rat brain areas between the distribution of enkephalinase and that of μ and/or δ opioid binding sites could account for most of the pharmacological effects elicited by enkephalinase inhibitors.

Journal Information

PNAS is the world's most-cited multidisciplinary scientific serial. It publishes high-impact research reports, commentaries, perspectives, reviews, colloquium papers, and actions of the Academy. In accordance with the guiding principles established by George Ellery Hale in 1914, PNAS publishes brief first announcements of Academy Members' and Foreign Associates' more important contributions to research and of work that appears to a Member to be of particular importance.

Publisher Information

The National Academy of Sciences (NAS) is a private, nonprofit organization of the country’s leading researchers. The NAS recognizes and promotes outstanding science through election to membership; publication in its journal, PNAS; and its awards, programs, and special activities. Through the National Academies of Sciences, Engineering, and Medicine, the NAS provides objective, science-based advice on critical issues affecting the nation.

Rights & Usage

This item is part of a JSTOR Collection.
For terms and use, please refer to our Terms and Conditions
Proceedings of the National Academy of Sciences of the United States of America © 1986 National Academy of Sciences
Request Permissions