Evidence for δ-opioid binding and GTP-regulatory proteins in 5-day-old rat brain membranes

M. Szücs, Carmine J. Coscia

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

The availability of the bispenicillamine enkephalin [3H][D-Pen2,D-Pen5]enkephalin [3H]DPDPE) a highly selective ligand for δ-opioid receptors, has made possible a more definitive examination of the ontogeny of this receptor sub-type. In this report, the binding characteristics of [3H]DPDPE in 5-day-old neonatal (P-5) and adult rat brain are compared. Analysis of saturation curves as well as homologous displacement data revealed no significant difference in the binding affinity of [3H]DPDPE between P-5 animals and adults. Conversely, the binding capacity increased fivefold during this period. The δ-specificity of the sites was further proven by competition experiments with μ- and δ-selective ligands. Mn2+ (0.5 mM) elevated [3H]DPDPE specific binding by lowering the Kd, whereas 50 μM 5′-guanylylimidodiphosphate inhibited it by decreasing the total number of high-affinity binding sites in both P-5 animals and adults. Pertussis toxin-catalyzed ADP ribosylation experiments revealed the presence of 40-kDa proteins, with a molecular mass corresponding to G protein subunits αio, as early as l h after birth. There was a low, but detectable, basal low-Km GTPase activity in P-5 animals, which increased fivefold during postnatal development. The present report establishes the existence of high-affinity [3H]DPDPE binding as well as GTP-regultory proteins 5 days after birth. Yet. heterologous competition studies and ionic effects suggest that neonatal binding sites differ from adult receptors. Whether the neonatal sites are newly synthesized, incompletely processed sites or a developmentally programmed isoform remains to be determined.

Original languageEnglish
Pages (from-to)1419-1425
Number of pages7
JournalJournal of Neurochemistry
Volume54
Issue number4
Publication statusPublished - 1990

Fingerprint

D-Penicillamine (2,5)-Enkephalin
GTP-Binding Proteins
Opioid Analgesics
Rats
Brain
Membranes
Animals
Binding Sites
Parturition
Ligands
Enkephalins
GTP Phosphohydrolases
Pertussis Toxin
Protein Subunits
Molecular mass
Opioid Receptors
Guanosine Triphosphate
Adenosine Diphosphate
Protein Isoforms
Proteins

Keywords

  • δ-opioid re ceptor
  • [H][D-pen,D-pen]enkeprialin
  • G protein coupling
  • Neonate
  • Ontogeny

ASJC Scopus subject areas

  • Biochemistry
  • Cellular and Molecular Neuroscience

Cite this

Evidence for δ-opioid binding and GTP-regulatory proteins in 5-day-old rat brain membranes. / Szücs, M.; Coscia, Carmine J.

In: Journal of Neurochemistry, Vol. 54, No. 4, 1990, p. 1419-1425.

Research output: Contribution to journalArticle

@article{f3c7c8cb415240f880064884a53456f3,
title = "Evidence for δ-opioid binding and GTP-regulatory proteins in 5-day-old rat brain membranes",
abstract = "The availability of the bispenicillamine enkephalin [3H][D-Pen2,D-Pen5]enkephalin [3H]DPDPE) a highly selective ligand for δ-opioid receptors, has made possible a more definitive examination of the ontogeny of this receptor sub-type. In this report, the binding characteristics of [3H]DPDPE in 5-day-old neonatal (P-5) and adult rat brain are compared. Analysis of saturation curves as well as homologous displacement data revealed no significant difference in the binding affinity of [3H]DPDPE between P-5 animals and adults. Conversely, the binding capacity increased fivefold during this period. The δ-specificity of the sites was further proven by competition experiments with μ- and δ-selective ligands. Mn2+ (0.5 mM) elevated [3H]DPDPE specific binding by lowering the Kd, whereas 50 μM 5′-guanylylimidodiphosphate inhibited it by decreasing the total number of high-affinity binding sites in both P-5 animals and adults. Pertussis toxin-catalyzed ADP ribosylation experiments revealed the presence of 40-kDa proteins, with a molecular mass corresponding to G protein subunits αi/αo, as early as l h after birth. There was a low, but detectable, basal low-Km GTPase activity in P-5 animals, which increased fivefold during postnatal development. The present report establishes the existence of high-affinity [3H]DPDPE binding as well as GTP-regultory proteins 5 days after birth. Yet. heterologous competition studies and ionic effects suggest that neonatal binding sites differ from adult receptors. Whether the neonatal sites are newly synthesized, incompletely processed sites or a developmentally programmed isoform remains to be determined.",
keywords = "δ-opioid re ceptor, [H][D-pen,D-pen]enkeprialin, G protein coupling, Neonate, Ontogeny",
author = "M. Sz{\"u}cs and Coscia, {Carmine J.}",
year = "1990",
language = "English",
volume = "54",
pages = "1419--1425",
journal = "Journal of Neurochemistry",
issn = "0022-3042",
publisher = "Wiley-Blackwell",
number = "4",

}

TY - JOUR

T1 - Evidence for δ-opioid binding and GTP-regulatory proteins in 5-day-old rat brain membranes

AU - Szücs, M.

AU - Coscia, Carmine J.

PY - 1990

Y1 - 1990

N2 - The availability of the bispenicillamine enkephalin [3H][D-Pen2,D-Pen5]enkephalin [3H]DPDPE) a highly selective ligand for δ-opioid receptors, has made possible a more definitive examination of the ontogeny of this receptor sub-type. In this report, the binding characteristics of [3H]DPDPE in 5-day-old neonatal (P-5) and adult rat brain are compared. Analysis of saturation curves as well as homologous displacement data revealed no significant difference in the binding affinity of [3H]DPDPE between P-5 animals and adults. Conversely, the binding capacity increased fivefold during this period. The δ-specificity of the sites was further proven by competition experiments with μ- and δ-selective ligands. Mn2+ (0.5 mM) elevated [3H]DPDPE specific binding by lowering the Kd, whereas 50 μM 5′-guanylylimidodiphosphate inhibited it by decreasing the total number of high-affinity binding sites in both P-5 animals and adults. Pertussis toxin-catalyzed ADP ribosylation experiments revealed the presence of 40-kDa proteins, with a molecular mass corresponding to G protein subunits αi/αo, as early as l h after birth. There was a low, but detectable, basal low-Km GTPase activity in P-5 animals, which increased fivefold during postnatal development. The present report establishes the existence of high-affinity [3H]DPDPE binding as well as GTP-regultory proteins 5 days after birth. Yet. heterologous competition studies and ionic effects suggest that neonatal binding sites differ from adult receptors. Whether the neonatal sites are newly synthesized, incompletely processed sites or a developmentally programmed isoform remains to be determined.

AB - The availability of the bispenicillamine enkephalin [3H][D-Pen2,D-Pen5]enkephalin [3H]DPDPE) a highly selective ligand for δ-opioid receptors, has made possible a more definitive examination of the ontogeny of this receptor sub-type. In this report, the binding characteristics of [3H]DPDPE in 5-day-old neonatal (P-5) and adult rat brain are compared. Analysis of saturation curves as well as homologous displacement data revealed no significant difference in the binding affinity of [3H]DPDPE between P-5 animals and adults. Conversely, the binding capacity increased fivefold during this period. The δ-specificity of the sites was further proven by competition experiments with μ- and δ-selective ligands. Mn2+ (0.5 mM) elevated [3H]DPDPE specific binding by lowering the Kd, whereas 50 μM 5′-guanylylimidodiphosphate inhibited it by decreasing the total number of high-affinity binding sites in both P-5 animals and adults. Pertussis toxin-catalyzed ADP ribosylation experiments revealed the presence of 40-kDa proteins, with a molecular mass corresponding to G protein subunits αi/αo, as early as l h after birth. There was a low, but detectable, basal low-Km GTPase activity in P-5 animals, which increased fivefold during postnatal development. The present report establishes the existence of high-affinity [3H]DPDPE binding as well as GTP-regultory proteins 5 days after birth. Yet. heterologous competition studies and ionic effects suggest that neonatal binding sites differ from adult receptors. Whether the neonatal sites are newly synthesized, incompletely processed sites or a developmentally programmed isoform remains to be determined.

KW - δ-opioid re ceptor

KW - [H][D-pen,D-pen]enkeprialin

KW - G protein coupling

KW - Neonate

KW - Ontogeny

UR - http://www.scopus.com/inward/record.url?scp=0025309693&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0025309693&partnerID=8YFLogxK

M3 - Article

VL - 54

SP - 1419

EP - 1425

JO - Journal of Neurochemistry

JF - Journal of Neurochemistry

SN - 0022-3042

IS - 4

ER -