N-Acetyl-β-endorphin1-31 antagonizes the suppressive effect of β-endorphin1-31 on murine splenocyte proliferation via A naloxone-resistant receptor

Nahid A. Shahabi, Michele Z. Burtness, Burt Sharp

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

High affinity binding sites for β-endorphin1-31 (β-EP) have been observed on transformed mononuclear cells such as the human U937 monocyte-like cell line and the murine EL4-thymoma line, and on normal murine splenocytes. Binding of β-EP at these sites is resistant to competition by naloxone and other opiate receptor ligands but sensitive to N-acetyl-β-endorphin1-31 (N-Ac), cations and GTP-γ-sulfate. Thus, the following studies were done to determine the functional significance of binding β-EP and N-Ac. β-EP suppressed phytohemagglutinin (PHA)-stimulated [3H]thymidine uptake in a dose-dependent, naloxoneinsensitive fashion. β-Endorphin1-27, (des)-tyrosine β-endorphin2-31, or N-Ac failed to duplicate the suppressive effect of β-EP. However, N-Ac, which is equipotent to β-EP at displacing 125I-β-EP bound to murine splenocytes or U937 cells, antagonized the suppressive effect of β-EP. Taken together with previous binding studies, the present observations suggest that β-EP effects receptormediated responses on normal immunocytes that do not depend on the activation of neuronal-like opiate receptors which are naloxone-sensitive. N-Ac, which shows minimal binding to such brain opiate receptors, is a potent functional antagonist of the naloxone-insensitive immunocyte receptor for β-EP.

Original languageEnglish (US)
Pages (from-to)936-942
Number of pages7
JournalBiochemical and Biophysical Research Communications
Volume175
Issue number3
DOIs
StatePublished - Mar 29 1991

Fingerprint

Opioid Receptors
Naloxone
U937 Cells
Thymoma
Phytohemagglutinins
Guanosine Triphosphate
Thymidine
Sulfates
Tyrosine
Cations
Monocytes
Brain
Chemical activation
Binding Sites
Cells
Ligands
Cell Line
naloxone receptor

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Biophysics
  • Molecular Biology

Cite this

@article{f8b55a1d4e8d4cb7b55dd9ed907460aa,
title = "N-Acetyl-β-endorphin1-31 antagonizes the suppressive effect of β-endorphin1-31 on murine splenocyte proliferation via A naloxone-resistant receptor",
abstract = "High affinity binding sites for β-endorphin1-31 (β-EP) have been observed on transformed mononuclear cells such as the human U937 monocyte-like cell line and the murine EL4-thymoma line, and on normal murine splenocytes. Binding of β-EP at these sites is resistant to competition by naloxone and other opiate receptor ligands but sensitive to N-acetyl-β-endorphin1-31 (N-Ac), cations and GTP-γ-sulfate. Thus, the following studies were done to determine the functional significance of binding β-EP and N-Ac. β-EP suppressed phytohemagglutinin (PHA)-stimulated [3H]thymidine uptake in a dose-dependent, naloxoneinsensitive fashion. β-Endorphin1-27, (des)-tyrosine β-endorphin2-31, or N-Ac failed to duplicate the suppressive effect of β-EP. However, N-Ac, which is equipotent to β-EP at displacing 125I-β-EP bound to murine splenocytes or U937 cells, antagonized the suppressive effect of β-EP. Taken together with previous binding studies, the present observations suggest that β-EP effects receptormediated responses on normal immunocytes that do not depend on the activation of neuronal-like opiate receptors which are naloxone-sensitive. N-Ac, which shows minimal binding to such brain opiate receptors, is a potent functional antagonist of the naloxone-insensitive immunocyte receptor for β-EP.",
author = "Shahabi, {Nahid A.} and Burtness, {Michele Z.} and Burt Sharp",
year = "1991",
month = "3",
day = "29",
doi = "10.1016/0006-291X(91)91655-V",
language = "English (US)",
volume = "175",
pages = "936--942",
journal = "Biochemical and Biophysical Research Communications",
issn = "0006-291X",
publisher = "Academic Press Inc.",
number = "3",

}

TY - JOUR

T1 - N-Acetyl-β-endorphin1-31 antagonizes the suppressive effect of β-endorphin1-31 on murine splenocyte proliferation via A naloxone-resistant receptor

AU - Shahabi, Nahid A.

AU - Burtness, Michele Z.

AU - Sharp, Burt

PY - 1991/3/29

Y1 - 1991/3/29

N2 - High affinity binding sites for β-endorphin1-31 (β-EP) have been observed on transformed mononuclear cells such as the human U937 monocyte-like cell line and the murine EL4-thymoma line, and on normal murine splenocytes. Binding of β-EP at these sites is resistant to competition by naloxone and other opiate receptor ligands but sensitive to N-acetyl-β-endorphin1-31 (N-Ac), cations and GTP-γ-sulfate. Thus, the following studies were done to determine the functional significance of binding β-EP and N-Ac. β-EP suppressed phytohemagglutinin (PHA)-stimulated [3H]thymidine uptake in a dose-dependent, naloxoneinsensitive fashion. β-Endorphin1-27, (des)-tyrosine β-endorphin2-31, or N-Ac failed to duplicate the suppressive effect of β-EP. However, N-Ac, which is equipotent to β-EP at displacing 125I-β-EP bound to murine splenocytes or U937 cells, antagonized the suppressive effect of β-EP. Taken together with previous binding studies, the present observations suggest that β-EP effects receptormediated responses on normal immunocytes that do not depend on the activation of neuronal-like opiate receptors which are naloxone-sensitive. N-Ac, which shows minimal binding to such brain opiate receptors, is a potent functional antagonist of the naloxone-insensitive immunocyte receptor for β-EP.

AB - High affinity binding sites for β-endorphin1-31 (β-EP) have been observed on transformed mononuclear cells such as the human U937 monocyte-like cell line and the murine EL4-thymoma line, and on normal murine splenocytes. Binding of β-EP at these sites is resistant to competition by naloxone and other opiate receptor ligands but sensitive to N-acetyl-β-endorphin1-31 (N-Ac), cations and GTP-γ-sulfate. Thus, the following studies were done to determine the functional significance of binding β-EP and N-Ac. β-EP suppressed phytohemagglutinin (PHA)-stimulated [3H]thymidine uptake in a dose-dependent, naloxoneinsensitive fashion. β-Endorphin1-27, (des)-tyrosine β-endorphin2-31, or N-Ac failed to duplicate the suppressive effect of β-EP. However, N-Ac, which is equipotent to β-EP at displacing 125I-β-EP bound to murine splenocytes or U937 cells, antagonized the suppressive effect of β-EP. Taken together with previous binding studies, the present observations suggest that β-EP effects receptormediated responses on normal immunocytes that do not depend on the activation of neuronal-like opiate receptors which are naloxone-sensitive. N-Ac, which shows minimal binding to such brain opiate receptors, is a potent functional antagonist of the naloxone-insensitive immunocyte receptor for β-EP.

UR - http://www.scopus.com/inward/record.url?scp=0025756935&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0025756935&partnerID=8YFLogxK

U2 - 10.1016/0006-291X(91)91655-V

DO - 10.1016/0006-291X(91)91655-V

M3 - Article

VL - 175

SP - 936

EP - 942

JO - Biochemical and Biophysical Research Communications

JF - Biochemical and Biophysical Research Communications

SN - 0006-291X

IS - 3

ER -